Back to the basics — Scope tips: Part 3

by Tom Gaylord
Writing as B.B. Pelletier

Part 1
Part 2

This report covers:

  • Droop — or downward slant
  • My point is…
  • I must care about this
  • Scope placement

This series examines the task of mounting a scope on an air rifle and sighting it in. Part 2 addressed mounting a scope, but it didn’t cover all of the problem areas, so today I’ll continue the discussion.

Droop — or downward slant

I will say that 80 percent of all the firearms and airguns I have examined have some degree of downward slant of their bores in relation to the line of sight of a scope that’s mounted on them. And I will go on to say that half of those are so serious as to cause problems. The airgun term for this is droop. The firearm world has no term for it and is generally ignorant of the problem. The single firearm that doesn’t seem to have this problem to the extent mentioned here is the AR platform. Perhaps the designers recognized the problem and solved it through engineering. I don’t know, but ARs seem to be relatively droop-free.

I used to think droop was an airgun problem; and like most airgunners, I thought it mostly affected breakbarrels. It’s easy to think that way. But all powerplants, including those with fixed barrels, will droop. And most of them do. The barrel isn’t actually drooping like a limp noodle — it’s simply pointed down and away from the scope’s line of sight.

About a year ago, while helping another shooter at my rifle range resolve a scope problem with his Remington 700 rifle, I realized firearms were also infected with droop. This guy had his vertical elevation cranked up as far as it would go, and he was still shooting low. Obviously, the fix was to shim the scope on top of the rear ring saddle and under the rear of the scope. That makes the scope slant down. We did and it worked, but not completely. We got him up to the point of aim at 100 yards with 2 shims made from soda can aluminum pieces, but his scope was still cranked up too high.

The real solution was to swap the rings front and rear. And if this had been an airgun, we could have done that. But his rings only fit the rifle one way, so that fix wasn’t possible. What he had to do was install a universal scope base (actually 2 small bases) onto which a Weaver scope ring would clamp.

After this encounter, I started paying attention to firearms with scope issues and my eyes were opened! Barrel droop is a universal problem!

Do you remember the Schuetzen rifle I mention acquiring a few weeks ago? I had it out to the range and had to dial the scope’s external adjustments as high as they would go to hit the target 10 inches below the point of aim at 50 yards. The bases on my rifles were the wrong ones, and one of them had to be exchanged to give the scope the correct downward slant. The scope is also way off to the right, so a lot of adjustment has to be dialed-in to get the group centered. In this case, whoever mounted the scope on this rifle was not a careful worker. The holes have to be redrilled for the correct bases and to align the scope properly left and right.

My point is…

When you mount a scope, believe that you’re mounting it on a drooper. That’s what I do when I mount scopes, and I’m seldom disappointed. This tip, alone, is worth the entire price of today’s report!

Here’s why my tip almost always works. If the gun is, indeed, a drooper, you solve the problem during the mounting process. No need to take the scope off and start over. If the gun isn’t a drooper, you just gained a lot of additional useful elevation adjustment. The bottom portion of the elevation adjustment range (i.e., adjusting the reticle down below the midpoint) does not put the scope in peril like the top portion (adjusting up above the midpoint) does. You can always adjust down, but going up is where the problems lie.

There are a couple rare instances where my tip won’t work. One is when the gun slants up instead of down. The other is when the gun is such a severe drooper that extreme measures have to be taken. You’ll encounter these situations with only a small fraction of the guns that are scoped. And both can be fixed the same way — if you have the courage.

I wrote a blog about Bending airgun barrels that addresses what must be done to correct a severe drooping or upward-slanting barrel. This will also work when a barrel points to the right or left, though I believe the scope mount should be fully explored before you try bending a barrel this way.

I must care about this

I have spent a long time today discussing one point of scope mounting, so I must think it’s important. You would do well to consider what I’ve said.

Scope placement

The next thing I’ll address is where the scope is positioned on the rifle. It has to be close enough to your eye so the full image can be seen when the rifle’s mounted on your shoulder in the usual fashion. Some scopes, like compacts and Bug Busters, are so short they can only be mounted close enough to the eye on a few air rifles. On most rifles, the scope stop location forces you to mount the compact scope too far forward, and the image is reduced to less than optimum.

The height of the eyepiece is another consideration. Some airguns, such as the TX200 Mark III, have ultra-high cheekpieces for high-mounted scopes. All the AirForce precharged sporting rifles use high-mounted scopes.

Other guns, like the Hatsan BT65 QE I’m now testing, have adjustable cheekpieces. This makes the rifle adapt to the high scope mount it needs to clear the magazine.

Hatsan BT65 QE
The Hatsan BT65 QE (seen here at the SHOT Show) has an adjustable cheekpiece to raise the eye to the necessary high scope.

Too many shooters obsess over mounting a scope as low as possible. A low-mounted scope on the right rifle is very convenient; but on the wrong gun, it is a disaster! And a large percentage of rifles are not suited to low scopes.

There’s no accuracy advantage to mounting a scope low. Shooters will tell you that the lower the scope is mounted, the less trajectory you have to deal with — and that can be demonstrated in software ballistic programs; but if you know your rifle, it makes no difference downrange. The only advantage I see to mounting a scope low is the lessening of cant as an aiming problem.

That’s my discussion for today.

146 thoughts on “Back to the basics — Scope tips: Part 3

  1. B.B.

    You said “A low-mounted scope on the right rifle is very convenient; but on the wrong gun, it is a disaster! And a large percentage of rifles are not suited to low scopes.” How do you tell if your rifle is suited or not suited for a low scope?

    David


    • Pa.oldman,

      I got the TX200 and (just now) shouldered it while standing several times. I had to lower my head (each) time to get good sight.

      While I have shot rested only, I will have to explore this more. I believe my rings are medium and put the 44mm. objective bell 3mm off the reciever.

      I may need to go with higher rings, for best “natural” shouldering. ???



        • TT
          I do believe I remember your conversation with Chris about that.

          That has been brought up to many times in the past.

          Its a easy thing to overlook that’s very important. The way you shoulder or hold the gun in your natural position will help with understanding how (cant) comes into play also and to be aware of it.

          Moving a gun around trying to find how to hold the gun right to see through the scope is definitely the wrong thing to do.


          • GF1

            You shoot better when you pull up and everything falls right in place . Otherwise you have to fight the rifle to shoot it . Does not work out so well.

            You going to raise a good crop of weeds in your new back yard ? Great seasonal targets .

            twotalon


            • TT
              I can just see me posting some pictures on photobucket of strategically planted sections of dandelions in the yard.

              You know all I would have to do is save the white seeds that blow all over the place from just one flower and have me a natural field target or mini-sniping course set up.

              And I would always have a great supply of targets I bet.


              • GF1

                Buckhorn is good too . Takes over when the dandelions fizzle out . Much tougher target . The stems are very narrow and blend in with the grass . You might have to settle for just shooting at the heads . The dandelion stems are fun . Hard to see, but not as difficult as the buckhorn.

                I like trimming big weeds too . A patch of poke is fun . You have to shoot a row of holes across a branch to cup it off . One large weed can provide a lot of entertainment if you trim it down the same way you would do a tree.
                You will have a scabby looking back yard, but it is the price you pay for hours of fun.

                twotalon


                • TT
                  I was just saying the other day that I shoot at branches in the woods that start intruding on my shooting area that I have cleared.

                  That’s at the house I have been living at. All I can say is its nice to not have neighbors that are close by. And I will even be more neigborless at the new house. Can’t wait to get done with the move and settled in.


            • Twotalon,
              Your comments have given me an insight on Chronys.

              The only creatures that have talons that I am aware of are owls and raptors, you must go through a lot of socks! Just kidding!

              Here are a couple of tidbits that you may find interesting. Over five decades ago, P.O. Ackley did a penetration test of three different caliber rifles against the frontal armor of a U.S. WWII half-track which was .5″ thick, the testing was at 30′ range. A 100 grain .270 Win. did nothing, two .30-06 AP (black tip) rounds only put shallow pockmarks in it averaging .084″ deep, the third rifle was a .220 Swift firing a 48 grain, soft point bullet. Both completely penetrated the armor plate, leaving approximately a 3/8′ diameter hole, speed kills!

              Being of German ancestry, you should be able to appreciate this, “the mother of all choked barrels”. Check out the “28 20 sPzB41” and its ammo, doesn’t it look like a huge PMM?

              Bugbuster



                • Twotalon,

                  You certainly are a man of few words. Five hundred, too many more and you would probably get the blooming petal effect accompanied by a much louder than normal report. I can’t even imagine the chamber pressure this beast would operate at.

                  Bugbuster


                  • Bugbuster

                    That thing squeezed down to 20 mm didn’t it ? I also thought about how high the pressure would be . Must have been absurd.
                    If all else fails, use the 88 .

                    twotalon


                    • Twotalon,
                      Yes it did,so did I, I agree, that was a good one also. The MV on it was up to 1,400 meters (4593 FPS) per second, the AP round had a tungsten core and resembled a Predator Metal Mag pellet on steroids! It was supposedly discontinued for lack of tungsten, it would have been devastating with DU.

                      Bugbuster


                  • That reminds me of the 25 and 30 mm armor piercing round we use to make at work.

                    Use to make the target practice round and the HEI round also.

                    The High Energy Incinarators are definitely bad boys that’s for sure.

                    And come to think of it we made the 20 mm rounds before we started making the 25 and 30 mm rounds.

                    Is that the rounds that you guys are talking about?


                    • Gunfun1,
                      I am not sure, I am not up to speed on U.S. ordnance these days, although I believe that the DU rounds are 25 and 30 mm which are used primarily in the Warthog (Thunderbolt) aircraft, Apache helicopter and Bradley fighting vehicle. I also believe that the Warthog and Apache use the multi-barrel G.E Vulcan cannon and the Bradley a chain gun.

                      If you assembled DU projectiles, or you would certainly be aware of it, they are like radioactive.

                      Bugbuster


        • TT,

          I remember talking about the wide FPS spreads, but not about scope height/mounts.

          As for rested shooting, it feels good and natural. And, B.B. said that you will be in different position with each type of shooting, so they are not the same.

          I would have checked it rested, but my shooting area is set up to chrony at the moment.

          If I missed a reply, I am sorry. I only go back about a day on the blog and delete the emails in the in box.

          As you might have seen, I am getting better chrony results with a lighting change. Got a 7fps spread with the latest pellet tested.

          Chris



            • T.T.,

              Thanks for the reply. As far as “if I can get it”,…it would seem that a given pellet, and a given gun, (are going to give you,…. whatever you get). And, as Gunfun mentioned awhile back,…just cause a pellet chronys good, does not mean it will group good.

              And, a correction on my original comment,…my rings are “high” as the box states.

              Also, my comment mentioned (standing) on my “check” this am, not rested. If I will ever shoot “off hand”, which I believe is the correct term, I will need to explore even higher than “high” mounts.

              I am 6’4″, so maybe the neck and head are “longer”, putting my eye higher than the average shooter. Who knows?

              Chris


              • Chris

                I also like the pellets that get the most power out of the gun. I have some that give me the most power, tightest spreads, and the best accuracy all at the same time.
                They don’t always work that way.

                twotalon


                • TT,

                  Ahhhh yes, that “holy grail of pellets”.

                  When I find it, it will be THE pellet I will stick with. Then of course, with adjustments, a heavy hitter,.. for max. down range “thump”.

                  Chris



                    • TT,

                      I must say that the PCP’s have my curiosity peaked, but I have a hard time getting past the “support” cost. I watched an episode of American Airgunner a while back and I swear BB said that it took 300-400 pumps on a hand pump and another 30-40 to keep it in the pressure “range”.

                      I could go the pre-filled tank route, but not sure of the services offered locally. The “tanks” are high dollar too and require checks periodicaly. Unless a smaller welding tank would do the trick,…but what gas?

                      Got a way’s to go go before I get there. Still got a TX to wear out first. 😉

                      Chris


                    • Bumped up one level as no “reply” remained

                      I must say that the PCP’s have my curiosity peaked, but I have a hard time getting past the “support” cost. I watched an episode of American Airgunner a while back and I swear BB said that it took 300-400 pumps on a hand pump and another 30-40 to keep it in the pressure “range”.

                      The number of pumps depends on the size of the reservoir vs the size of the pump…

                      As a rough number, the tanks on my AirForce Condor want 15 strokes per 100PSI — so 150 strokes to go from 2000 to 3000 PSI.

                      My Marauder wants 10 strokes per 100PSI. I need to reshoot the power curve (since I’ve discovered the Marauder’s gauge reads high), but the last time I did it I’d concluded that 2700-2200 (by its gauge) was the usable range. That’s 500PSI, or 50 strokes to refill from the bottom end.

                      My Silhouette pistol takes 5 strokes per 100PSI.


                  • Chris,USA
                    By far the cheapest route to go with PCP is to find your local welding gas supply company and inquire about the cost of renting a 120 cubic foot tank either of compressed air or better yet Nitrogen as they both will hold 6000 psi and on an average PCP gun of 200CC cylinder volumes it comes out to 117 fills when filling to 2900 psi and refilling at 1800 psi.

                    I now in my area it is 55 bucks a year to rent the tank and 50 to have it refilled. You would still need the adapter to attach to fill the gun but for 300 bucks including tank rental and fill adapter you could be shooting a PCP and 117 fills is a lot of shooting.

                    BD


                    • BD,

                      AWESOME info ! (Notes made). I have weld supply shop about 2 miles from work. 300$ + gun is reasonable.

                      Still thinking about it at this point, but just the kind of info. I needed to ponder a PCP.

                      Thank you, Chris

                      P.S. Missed ya’ ,…glad your still here! 😉

                      Chris


                  • Chris,USA
                    I was out of town over the weekend as I went to the beach with a friend down to Gulf Shores , AL and got back Tuesday. I don’t use or have email on my phone as I cannot read that little screen without major eye strain so its a 23 inch screen for me or no email or blog posts.

                    I will be out of town the middle of next week as well with the same friend as we are going to Ohio to pick up a motorcycle he just put a down payment on and since we will be 3 hours from PAs store he has agreed to go there as well so I can stock up on pellets and possibly a new compression chamber and piston for a TX to put in my B40.

                    The bike we are picking up is a Boss Hoss 2007 model which I don’t know if you are familiar with but it is a brand of bikes that use chevy V8s as engines and the one he is getting is the last year for the 502 cubic inch big block motor with 502 horsepower. it has a 300mm by 18 inch diameter rear tire and two speed auto tranny with second being an overdrive of .88 to 1 , it will do 120 mph in first gear and then you shift to second and the speedo goes to 160 and it will bury it I am pretty sure. It will smoke the rear tire at will to 120 mph and likely past that as well. You cannot shift into second until you are over 55 mph or the torque of the motor will damage the trans. It has been his dream to own one and it is coming true for him, and I would be comfortable in saying that it the king of the road where motorcycles are concerned.

                    BD


                    • B.D.,

                      I’m with you on the whole phone thing. Not for me.

                      Yes, I have seen a Boss Hog at a big biker party back when I had the Wide Glide. Wayyyyy too much bike for me. While maybe a bit wilder in your younger days,…I think you might still have a “few screws loose”. 😉

                      I did not know you could go to P.A. direct. Do they have a retail store or is it something special you have set up? My sister lives within a half hour of there, about 2 hrs. from me. I’m central Ohio.

                      Take care and have a safe trip getting the bike.

                      Chris


              • Chris

                You pretty well have figured out the PCP support problems. The only gas other than air that you can use is nitrogen. Some have tried helium, but it costs and because of the small molecular structure it can leak .
                You also have to be careful of high pressure fill sources. You can easily over fill .

                PCP are the worst for testing pellets and plinking. Once you get one set up for hunting, you can use a hand pump without much problem . Unless you are doing a really good day of pest shooting, you just don’t need to fill very often.
                I think the most chucks I have gotten in one day was 8 . That’s less than half a fill.
                I have had some fast and furious days of starling shooting that had me filling 3 times a day , but this is not the norm.

                twotalon


                • TT,

                  Thank you for that info. It will be a while.

                  The one thing I’m afraid of is myself,….my first time out,…I went for the TX,..( and am glad I did ). With a PCP,..I see going for one of those 1500$ shooters.

                  I live simple and work hard and don’t often treat myself to much. The TX was the first in a long time. I just know I like quality and getting the most bang for my buck.

                  Believe me,..before I do get one,..I will have about a “Bazillion” questions, so look out !

                  At least I know where to go…… 🙂

                  Chris


                  • Chris,USA
                    Yes the phone is just that a phone.

                    Unfortunately the Boss Hoss is not for me but is my friend that is buying it and he is 6’1″ and around 280 pounds so he is a big boy. what most people don’t realize is the center of mass in a Boss Hoss is about 6 inches off the ground so it can be laid over on its side and picked back up to vertical with one hand as it only moves to around a 60 degree angle due to the wide girth of the engine. If it was me buying it I would be in jail or dead in short order as I only know one throttle position and that is WFO.

                    I thought there was an actual store but now that you mention it I need to check that for sure as I just assumed there was a brick and mortar store. Thanks for giving me a heads up on that so we don’t drive there for nothing. the bike is in ST. Marys, Ohio and PA is in Solon, Ohio .

                    BD



  2. I’m currently having issues getting my qb-36 dialed back in after removing its original Red Star 4×20 peephole and attempting to use a 4×32 Centerpoint that came with the Regal.I carefully explored the limits of the adjustments and then patiently awaited this blog.
    B.B.,
    Thank you so much for all you do here!
    I’ve been pretty quiet recently but that’s just because it’s so much harder for me to type on this phone than using an actual keyboard but come May I’ll be receiving the rest of my back pay and should ‘ve able to get the computer hooked up here.
    Please let us know what’s available to help resolve these issues in terms of adjustable rings or inserts.Hopefully PA will carry some or all of this hardware so we don’t need to search for it elsewhere.

    Reb


    • Reb,

      While B.B. may have a different opinion, I have read where some scopes can be damaged while checking the full adjustment ranges. I did this on a Leapers scope and the windage got stuck at the full right/out position. The elevation was fine,..despite the useing the SAME carefull and easy method.

      While I would like to do this, I did not do it with the new scope. I also called Leapers and they said that their scopes come “centered” from the factory.

      But really, if you get a used scope, you have know way of knowing (where) the adjustments are at (without) doing this.

      So what do you do? Mount and shoot?



        • Ok BB I got to jump in here and ask this question.

          You just shoot you say. Ok that’s great but what I want to know is how do you know where your turret is if you have a scope that doesn’t have the turret knobs that move up or down and show the reference lines. You know those scopes that just click the dail when you adjust up/down or left and right.

          After you just shoot how do you know or maybe I should say how does a less exsperianced shooter know if he is getting away from the turret spring tension that we know causes problems with the reticle trying to float.

          Can you please explain to them how to know they are getting to have that problem by just shooting.


          • GF1,

            First of all, I avoid scopes that adjust that way like the plague. They are invariably cheap and cause the problem you mentiopn. But I do own some of them.

            My solution is to :

            1. Just mount the scope and shoot.

            2. If it is shooting wild, I crank the adjustment up as high as it will go. If that doesn’t take very much adjustment I know that scope was adjusted high to begin with and I go from there.

            Like I said, scopes that have such adjustments are the cheapies and I always suspect them of failing.

            B.B.


            • BB
              I agree. I can’t stand those type of scopes at all myself.

              And what you just explained would now give a shooter something to try and to be aware of rather than just shooting.

              The bottom line is one way or the other.

              You will need to determine where your adjusted at in the turret travel I will call it so you don’t start floating the reticle.


              • GF,

                Glad to hear you are getting moved. You must be taking a break or taking a day off.

                I do hope you are taking a vacation while moving. I would hate to think you are moving and still working at the same time. If so, you will be ready for a week long nap when you get done. 😉

                Take care, Chris


                • Chris, USA
                  I’m off from today till next Tuesday and the wife had to work today. And the kids where in school.

                  I boxed some stuff up this morning and got the washer and dryer out of the basement.

                  And I said the heck with it and got me a little shooting time in.

                  But getting ready to load up in a bit and then its all on till we get it all over there.

                  Hope to have it all there by Sunday afternoon.

                  And hopefully I can get back to normal. And thanks.



    • I believe I’ve nailed it! 10 shots of Crosman pointed (not it’s favorite)stayed inside the .5″ bullseye@ 5 yds. I was informed by one of taintenence men who spotted a tin of pellets that discharge of firearms is illegal in the city limits yesterday and told him there was no powder involved,I guress he was making sure I knew better than to be shooting on the grounds. Turns out old t-shots and socks stop most pellets pretty well when stuffed inside an empty 12 pack box placed in front of my .5″ plexiglass cutting board!


    • Reb
      The easiest way I have found to know just where a scope is set at as far as the centering of the reticle is concerned and take all the GUESSWORK out of the equation is to optically center it using a mirror and it can be centered in less than a minute and that way you know exactly that the scope is in its centered position so when you first shoot the gun you do it at 30 yards with the scope centered and where the pellet hits compared to your point of aim will tell you if you have any droop or not.

      To optically center the scope just get any mirror that can be held up to the objective end of the scope with the magnification at its lowest setting and the adjustable objective set at infinity. When you look thru the scope you need a bright light over head or if possible out in bright sunlight and you will see the distinct dark reticle and another set of lighter colored ” ghost reticles ” that unless the scope has already been optically centered will be clearly visible as a second set of crosshairs. while looking thru scope adjust the windage and elevation turrets until the ghost reticles are lined up exactly with the dark fixed reticle in the scope and it is centered.

      Then when you shoot the gun at 30 yards which is the standard most all scope mount makers use as a distance to determine amount of droop correction you will know just how much if any droop you need to correct for and doing it this way will prevent a lot of chasing your tail when trying to get a gun sighted in.

      BD


  3. Holy mackerel, BB!
    That whole “treat every rifle as a drooper” thing sounds like a good way to solve a lot of problems. Instead of expecting everything to be perfect, you count on it to have a few simple-to-fix problems, fix them, and wind up with something far better than you’d have had before.
    Even better is knowing the quickest solution for these problems and having them handy in a shooting bag or tool kit.
    A few beer-can shims would only take seconds to make up ahead of time, especially if you’re already making some. Another thing I have found to be useful is small “ribbons” made from a party balloon, to add grip to mounts or rings without adding significant thickness. Don’t forget your blue Lock-tite!


  4. On a side note:
    I have submitted a couple of bug reports to Pyramyd, and am getting “Failed delivery” notices in my email. I was trying it through the “5% or 200 Bullseye Bucks” page, so I figured I would just post them here and wait for those points to arrive. 😀

    ********************************
    Subject: Find an issue on our site – earn a 200 Bullseye Bucks! CustomerID: 227203
    From: Q Jay

    I was searching for Benjamin pumpers, entered 397 into the product search bar, then clicked the Benjamin link on the left side of the page, then tried to remove the 397 filter, and I found the page Pyramydair.com/NaN which means 404 error to most folks.

    Anyhoo, I’m already signed up, and I love your site, and I really appreciate everything you folks do for the airgun community, so I figured I would mention it when I saw you have an actual bug reporter, aka “the 5 percent or 200 Bullseye Bucks” thing.

    Thanks! QJay
    *************************************

    That’s only one thing, you may have noticed, the other is the bug with the bug reporter not working correctly. 😉

    I do see a message about problems from Yahoo.com, and since my email is from there, that may be what caused the bug reporter to fail, in which case, it would be pretty simple to add a whitelist to that bug report page: Just allow reporting from the addresses of any actual account holders. Problem solved?

    Thanks again! ~QJay


  5. Good morning BB,
    Have you ever done a side by side comparison of the Airforce Edge and the Crosman Challenger regarding shots per fill, accuracy, adjustability, ergonomics, etc.
    Also have you heard anything about the new JSB pellets in .22 and.25 and will you be reviewing them along with the other heavyweight pellets in the test we spoke about in November.
    Thanks for another great blog entry.
    Azhar


    • Azhar,

      I didn;’t do a side-by-side comparison, but I did review both air rifles.

      Here:

      /blog/2010/02/airforce-edge-part-7/

      And here:

      /blog/2009/11/crosman-challenger-2009-target-rifle-part-5/

      Part 4 of the Challenger report is not linked. We will look into that.

      B.B.


      • Also have you heard anything about the new JSB pellets in .22 and.25 and will you be reviewing them along with the other heavyweight pellets in the test we spoke about in November.



          • Hello
            I am not speaking about the 18gr heavies or the 25gr monsters, rather I am speaking about the newest ones which have not been launched yet and will be +/-30gr.
            Also what do you think of the other heavy weight pellets on the market for use in an airforce condor such as the Prometheus/H&N piledrivers, H&N rabbit magnums, etc.
            Have you done a heavy weight pellet test focusing only on these heavy pellets in powerful airguns and a comparasion to the more commonly used shapes, styles and weights?in terms of accuracy, long range accuracy, etc.
            Azhar


  6. I have seen the “universal droop” problem. Even among my small but growing gun collection I don’t remember even once having to crank the elevation adjustment down–it always seems to start off shooting low (some VERY low) on a new scope installation. I’ve also found that I’m always making way more vertical adjustment than horizontal.

    It seems to me that metal shims from aluminum soda cans might mar a scope’s finish. What are some other material suggestions? I do recall mention of plastic shims from 2 liter soda bottles. The non-slip shims installed on Leapers/Accushot scope rings seem like they would be ideal, but I haven’t seen anything like that commercially available.




      • B.B. and all,
        You can purchase a plastic shim assortment from MSC and probably McMaster Carr, the one I have came from MSC. There are a total of 14 pieces 5″X20″ and are color coded. The sizes are as follows: .0005″, .001″, .0015″, .002″, .003″, .004″, .005″, .0075″, .010″, .0125″, .015″, .020″, .025″ and .030″.

        Personally, I do not like using plastic shims made from disposable containers because most of them deteriorate over time due to UV, ozone or a combination of the two. It may not really matter though for this application, since once in place, very little material is exposed, just saying.

        P.S. B.B. Sometimes I do not answer your reply to my reply or inquiry, please forgive me for that. The reason is to lessen your workload and put more unnecessary comments on the blog. I honestly don’t know where you find the time to do everything that you do. Testing, writing, reading/answering questions on the blog and still being able to eat, sleep and do all else necessary in life! I am truly amazed!

        Bugbuster


        • Bugbuster
          We use those plastic shims at work shimming the cutting tools for center height.

          I myself don’t like a thick shim (anything over .010″) under the scope on the back ring. The shim will cause the scope angle to not be true to the ring saddle. That gives you a possibility of damaging the scope tube.

          That’s why there is mounts and rings that have the correct angle made into them.

          That’s one reason I’m interested in Cal’s scope bedding technique he came up with. He suppose to be doing a guest blog.


          • Gunfun1,

            You are preaching to the choir here and I agree with you 100%! I have only done it once, just for those very reasons. That was a very long time ago for a friend. I had to put a brass shim between one of the bases and the receiver, but never in the saddle of the rings. Of my three scoped, high powered, springer AGs, all have one piece RWS droop compensated mounts. The other two have one piece cantilever mounts which do not. One is a UTG and the other a BKL, both are cradling Bugbuster 3-9x32mm compacts. After I have them mounted in the rings and locked down, I take a soft lead pencil and scribe lines on the scope body along the ring clamps to monitor for scope creep.

            Bugbuster



      • Try linerless rubber electrical splicing tape for scope shims. It is extremely flexible rubber .030 in thick. Buy a roll that is a half inch wide and you’ll have a supply of scope shims for a lifetime.


  7. B.B.
    It is well known that you are a big fan of the one piece drooper mounts, either BKL or RWS. However, have you ever tried two piece drooper mounts? I know FX “No Limits” 2 piece mounts and Sportsmatch ( from the UK) make some as well…any others?
    One the one piece mounts, is the angle of drop adjustable? What about lapping scope rings?
    Thanks,

    Yogi


    • Yogi,

      No, I have never tried 2-piece drooper mounts — though I do use different height scope bases on some of my vintage firearms. I will talk about that in a future report.

      As for lapped rings, I know some people swear by them. I don’t know enough to comment.

      B.B.


    • I’d be wary of a two piece “drooper” as the angle of the surfaces of the rings would only be correct at one spacing of the mounts.

      At any other spacing, you’ll have one edge of the ring digging into the bottom of the scope tube, while the other edge digs into the top.


      • Agreed! But is this a big deal? If you move scopes around I guess.
        Plus you get more adjustment, some even have windage adjustments. I have not seen that with a one piece mount! Also, max angle is usually 2mm or less. Not great with large objective scopes either.
        Just curious if anyone has tried them. Heck if they are from FX, they may not even deal with magnum springer recoil very well.
        Thanks,
        Y



  8. BB– My obvious solution is to use Burris Signature rings with offset inserts. They do not mar the scope finish and will not bend the scope. I think that you will like them, once you try them. Ed


  9. Great article and series BB, I’d never have thought that droop would be present on anything other than a breakbarrel.

    Kevin in CT (Where it has finally stopped snowing!)


    • Kevin in CT.,

      3″ in Ohio on Tues. 🙁

      Getting some good chrony results on 7 types of pellets. I will let you know when I am done.

      Plus, some grouping info. as well. Maybe save you a little $ on buying lead to try.

      Chris


  10. B.B.
    I have found that my magnum springer was more accurate when the scope was mounted to the dove tails on the action. The scope stop was inadequate and had to switch to a weaver adapter which meant that the scope was mounted higher. The rifle became more unruly and require a lot more technique to produce good groups ( perhaps the higher center of gravity is the culprit ??). Has anyone else had this problem??

    Pete


    • Pete

      When I first got my 48, I was going to use a scope for pellet testing, but I ran into similar problems.
      The 48 is a serious drooper, and required a droop adapter . Even with low mount rings, the scope was way too high . Rifle was top heavy and unmanageable for a good hold.

      twotalon


    • Sounds more likely to be from canting than Amy other influence. Am addotipnsl .5″might be responsible for change in elevation depending on the range being shot at but that’s all that shouu change as long as all(s locked down.I wouldn’t expect shifting POO unless someone is slipping or differmce in hold


  11. Let me open a controversial can of worms (probably parasitic nematodes)…

    While I’ll accept that manufacturers may have a consistent mis-alignment in fitting barrels (and given the cost of machining, probably are using the same equipment for decades)…

    How much “droop” could one blame on the short distances used for air guns?

    That is — even if the barrel/bore and receiver were perfectly parallel, the scope (especially with the large objectives and high powers so many air guns end up with) could be over 2 inches above the bore line.

    If one takes the sight line as the hypotenuse (hence ignoring bullet drop), and a 25 yard zero as a typical set-up, one obtains a right triangle of 2″ x 900″… Tangent value of 2/900; arctan(2/900) => 7.6 arc minutes.

    Take the same 2″ height, but use a short firearm zero (100 yards — the fixed parallax on the scope I mounted on a .44Mag lever action is all the way out to 150 yards; going to be fuzzy at my expected 1.9 arc minutes.

    We end up using a lot of the elevation range of the scope just to compensate for the short zero distance, before even getting into trajectory and “droop”.

    I don’t even want to consider calculating the effects of a short zero on something like the Condor.



      • Take the same 2″ height, but use a short firearm zero (100 yards — the fixed parallax on the scope I mounted on a .44Mag lever action is all the way out to 150 yards; going to be fuzzy at my expected 1.9 arc minutes.

        Somehow that paragraph seems to have gotten trashed. Should read “… at my expected distances) …” and then have the equations (2/3600) working up to 1.9.

        I’ll have to confess I don’t have enough experience at longer ranges… The longest I got with my Browning A-Bolt (.308Win, using cheap 7.62NATO Ball) was a 50 yard range (because I was also trying to sight in a Condor and Marauder, and a Ruger 77/17, that day). Then got laid off before I ever got back to the range. {and of that day — the A-Bolt had the tightest groups: fox squirrel size}

        I still need to see if the local range will allow the .44Mag lever action (technically, they are a pistol range, max 25 yards). Based on some ballistics software, and an estimate for the velocity increase from a carbine barrel, a 25 yard ascending zero should be a close match for a 75 yard descending zero. But a 150 yard parallax at 25 yards is not going to be very pleasant.


  12. B.B.,

    I heeded your warnings about droop and remounted the scopes on two air rifles with BKL Droop Mounts and saw a significant improvement in accuracy. I’m a believer.

    Droop is a scope problem, too. Scope manufacturers must address this problem with reliable adjustments throughout the scopes adjustment range, and airgun and firearm manufacturers must address the problem, too.

    Thanks,

    RB


  13. One thing I think people who are aware of droop overlook is ballistics.

    If I take a gun that shoots a 7 grain pellet at 900 fps that is zeroed at 30 yards and shoot it at 30 yards and hitting the bullseye dead on.

    Then take that gun and shoot a 14 grain pellet that obviously weighs twice as much and (don’t) rezero the scope and aim at at the same bullseye at 30 yards away the point of impact should be lower.

    And not just a little lower. I would say 5 to 9 inches lower. So then at that point in time I would have to adjust up clicks in the elevation.

    That could seem like droop to somebody. And to top it off how would I know where the elevation turret is adjusted at if I never checked if the reticle was centered with that higher velocity lighter pellet when I zeroed at 30 yards.

    If that heavy pellet was hitting 9 inches low I would think I would need a few turns of up. And I bet I would be getting closer to the dredded reticle float.


  14. Thank you getting ready to mount a new scope. I have a preference for fixed power scopes, bright clear and usually robust. it really helps to begin with all firearms and airguns are droopers. Otherwise you fret you have a lemon of a gun. All mine droop I don’t stress just get a droop comp mount to begin.
    Can you come to further on pellet weight in grains equals foot lbs sweet spot? Real or imagined?


  15. Rob,

    I’m not sure I understand what you are asking. The fact that the pellet weight in grains equals the muzzle energy in foot-pounds at 671 f.p.s. is a mathematical coincidence. But knowing about it gives me insight into how some airguns are performing, as I indicated.

    Incidentally, 949 f.p.s is the velocity at which the twice weight of the pellet in grains equals the muzzle energy. For example an 8 grain pellet moving 949 f.p.s. produces 16 foot-pounds.

    B.B.


  16. I have to laugh with you guys – weeding the lawn with a pellet rifle – been doing that for years. Now I don’t feel so “strange” LOL!

    Can I admit out loud that I am buying a Bug-Buster scope for my FWB 603 for eradicating tent caterpillars (one at a time of course – one must be sporting about such things  ) ?

    More seriously, for much of my rifle shooting I shoot instinctively – the way you would a bow without sights – and the gun sights are used only for reference and focus is only on the target. I aim before shouldering the rifle (or drawing the bow) and shoot (release) the moment the sight-picture is correct – pretty well immediately. For this type of shooting gun “fit” is critical and I have never hesitated to rasp/pad/modify a stock until it shoulders on-target. I am just finishing a new stock for my AR20 because I could not get the original stock to feel right (besides there was too much snow on the ground to go shooting and I don’t prefer plastic stocks).

    Instinctive shooting works great for hunting situations for quick shooting at reasonable distances. I used to shoot respectable scores on skeet – with my .22 rifle – back when burning through 2 or 3 bricks of ammo in a morning was typical.

    For longer shots, small targets or formal target shooting I will pay more attention to the crosshairs but windage and hold-over are still done unconsciously.

    The crosshairs on my first scope did not optically center in the tube so I had to mechanically center them and make 90% of the adjustments to the mounts to get it to look reasonable. Still have the habit, I’ll optically center the scope, then shim as required to get close before making fine adjustments with the turrets. Think that is why I have not run into problems with the scopes losing their zero. Fixed a lot of “inaccurate” rifles with a good cleaning and remounting the scope.

    Yeah, and I am not kidding about the Bug-Buster scope …back to work.

    Vana2


    • Vana2

      Setting up your target stand right next to a soybean field will get you plenty of bug wacking action too. These beans are full of all kinds of bugs.

      When I was doing some gardening, the big tomato hornworms were great targets. They pop and deflate real good.

      twotalon


    • Vana2
      Back when I was a kid growing up on the farm that is pretty much the same thing I did with my semi-auto .22 rim fire rifle.

      We use to throw the old empty oil cans that were made out of a type of cardboard with a thin metal top and bottom up in the air and see how many times we could hit them before they hit the ground.

      I never even knew what a scope was until I was in my teens. My dad taught me when we were plinking to look at your target with both eyes open then point the gun above the target and come down on the target and pull the trigger when you had your full target pictured. No time for shake that way.

      When I shoot my semi-auto FX Monsoon at my Caldwell metal spinners fast shooting I use that same type of sighting even with the scope on the FX. I just start from the side of the first of the 4 spinners and go across then come up and over to line up with the top 5th spinner that resets the 4 others. I have 2 of those types of spinners I set out in different places in the yard and use that method to find and shoot them.

      That adds a little excitement to shooting. And I have pretty good success shooting mice in barns with the FX using the quick sight point of aim technique even with the scope on the Monsoon.


      • Hi GF1,

        I am more “methodical” in my shooting now but there are times that I miss the blaze-away firepower of a .22 semi-auto to ravage a bunch of cans.

        Yup, done the oil-can thing as well. We used to have rubber-ball races to see who could roll the ball to the finish line first or roll it the farthest. “Walking” a can through an obstacle course is fun and the target-in-a-tire bounced down the hill was good practice for deer hunting. Back then I only shot paper to sight in.

        Used to have a Mossberg Model 352KC – that was the one that had a fore-stock that pivoted down to become a grip. That one could use shorts, longs and long-rifle ammo. Really enjoyed that rifle, it was my “go-to” for years, ended up selling it to get a Belgium made Browning T-Bolt .22. After reading BBs review with the Ruger I think I am going to see how well the T-Bolt will do at 50 yards. Will do my own PCP/rimfire test. 🙂

        When I was researching for a general target/plinking/hunting PCP I looked at the FX products in detail. It was a toss-up between the FX Royal 400 and the Weihrauch HW100. Ended up with the HW100 and am extremely pleased with it. Fits me perfectly, great balance, supper trigger (as good as my FWB 603!) and awesome accuracy. Very smooth operating side lever and magazine. Can’t wait to get it out for some serious shooting.

        Snowing here, hope you guys have better weather!

        Vana2


        • Vana2
          We would do the can races also. Never did the obstacle course thing but we would try to keep the can moving till the whole magazine was shot without missing.

          That was one of the reasons I got the FX Monsoon for was some good old fashioned as fast as I can pull the triggerfast action plinking and its a .22 cal. also. And I will say this one is very accurate. It will way out shoot my old Winchester 190.

          And thank goodness no snow here but the high is only going to be in the 40’s today and tomorrow. Then back to the upper 60’s Sunday. Hopefully that should be getting close to all warm weather pretty soon.


  17. BB,

    I have never used a scope. Somehow when I think of them, in my mind it seems to take away the sportmanship of the rifle. It maybe that I have a purists attitude and I am missing out on a great experience. As I do not do long range shooting (only 10 meters) I would appreciate your opinion on using a scope at this short a distance.

    Btw, I tried the hobby pellets….they worked great….managed a 5/16 and a 6/16.

    Thank you…..



    • Lady-katie, I don’t think you could shoot at a shorter range than I do which is 5 yards for my airgunning. Most of my shooting is done with scoped rifles, and they give me great satisfaction. The challenge remains. I know when I’m shooting better or worse. The scopes are easier on the eyes and in fact, may allow you to work more on your skill by giving you more details of the gun’s movement.

      As for the challenge of open sights, I think a certain amount of that is overcoming equipment flaws. There are many variables about whether the front blade is too wide or narrow relative to the rear sight and whether the sights are clearly defined or fuzzy as they might be with fiberoptic sights. I don’t know if those challenge your shooting skill or just serve to distract. Scope reticles make it simple, so it’s just you and the target.

      Sportsmanship is a very relative concept that is up to the individual. Perhaps you’ve seen the film Orca where Richard Harris hunts a malevolent Orca. When the final showdown comes, he pulls out depth charges, but his girlfriend convinces him that this is unfair. So, he resorts to a harpoon. Later he makes use of a shotgun, but by then it is too late, and it doesn’t end very well for him. How hard do you want to make it for yourself and why? I guess challenge is a deeply personal thing. But scopes will not put your shots on target. That will still be up to you.

      Matt61


      • Matt61,

        What a wonderful perspective you have regarding the scope. Would you please let me know what type of scope you are using. You have peaked my interest……thanks!!


        • As you can see, there is a weight of opinion on the other side of the value of short range scopes. The fact is that I use both open sights and scopes interchangeably. But, I will add another point that I didn’t mention which is that scopes look cool. 🙂 Before I got into shooting seriously, the image of a shooter with a rifle and scope had a mystique which has never disappeared for me. There’s a current wisdom that the latest advances in shooting are not so much in the gun mechanism which has been unchanged for decades but in accessories, especially optics. And could it be that the advances are not just in reaching out further, which was the original purpose of scopes, but operating at closer range? The fact is that only new scopes can focus at the range I shoot at. And it is something of a surprise that they adjust for my elevation.

          Equipment is key. To answer your question, I use UTG Leapers scopes exclusively. I think the Centerpoint brand, which I also have, is an affiliate. Specifically, I use the Bugbuster

          https://www.pyramydair.com/s/a/UTG_6x32_AO_Bug_Buster_CQB_Compact_Rifle_Scope_EZ_TAP_Illuminated_Mil_Dot_Reticle_1_4_MOA_1_Tube_Medium_Weaver_Rings/4699

          and a 4X32mm model

          https://www.pyramydair.com/s/a/Leapers_UTG_4x32_AO_Rifle_Scope_Mil_Dot_Reticle_1_4_MOA_1_Tube_Weaver_Rings/4315

          Matt61


        • Lady-Katie,

          Hi again. If you do get into scopes, be prepared in trying to learn a lot. It does add a lot of fun and really gives you an upclose look at your target. I like it. Open sights would be good for casual target practice. You seem that you are really trying to get the very best and challenge yourself.

          But remember what B.B. said,….it may be the best you can get with the gun that you have. There is a lot more to accuracy than a scope or open sights.

          Chris


  18. (Note: my 1st attempt said it didn’t go through, so this is a re-post; if you get two, please delete one; thank you!)

    B.B.

    Reading this made me think of one more thing about scope mounting (that you are most likely about to address in Part 4, or 5, …or 10 *lol*). I was testing a Stoeger X20S that I just received from PyramydAir last night, and after about 20 shots, I could see that the scope had moved back about 1/8″ although the mounts (the back one is pinned, I believe) stayed in place. On my way home from work tonight, I’ll pick up a roll of double-sided tape (the kind used by machinists) and put a piece under the top portion of each of the scope mounts. That’s what I did for the scope on my HW97 back when I was shooting Field Target (and a couple of my friends’ guns as well) and it never moved.

    By the way, I would like to see a blog some day about the Stoeger X20S; I’d never even heard of it till a few days ago; but armadillos are destroying our back yard (and my wife is not happy!), so I did a search on Pyramyd’s site for a powerful but quiet air rifle in the “2” range for noise, and that gun kept popping up. Most of the reviews on it were pretty favorable, like “good power, good accuracy, but could use a better trigger and better scope.” The complaints seemed to come from people who wanted to bench rest the gun…God alone knows why, it’s obviously not meant to be a target gun. *shrugs*

    I’ll post a review after I do some more testing, but, so far, I am impressed. The gun came nicely packed in foam in the factory box, which PyramydAir had then totally repackaged in another padded box; so yes, the gun arrived in great shape, which is much appreciated. Standing, offhand, on my indoor 5 meter range, I was getting sub half inch groups when I wasn’t even trying for accuracy, just testing the power (I buried Crosman pointed pellets .600″ deep, to the back of the pellet, in a pressure treated outdoor 2X4…impressive…it will definitely do the job!).

    Once I tweak the scope with the double-stick tape and let the gun settle in, I’m looking forward to some good accuracy. As to the trigger, maybe I lucked out, or perhaps Stoeger is listening to the air gun blogs; I did not see the long unpredictable 2nd stage I’d read about; instead, I saw a nice 1st stage (about 3/8″, good for safety) and a short, predictable second stage.

    And the best thing about this .22 is that I CAN buy ammo for it; PyramydAir’s got tons of it! *lol*

    Anyway, these guns seem to be pretty popular for those of us who have to shoot in the suburbs and wish to remain stealthy so as not to alarm our neighbors. I’d be curious to know your thoughts on it; thank you.

    take care & have a blessed day,
    dave


  19. Barrel droop, like parallax, is one of those things I’ve never really figured out, so this seems like a good time to try again. So, the droop is not a curve but a straight line which deviates from the barrel axis. That’s an advance! But it raises more puzzling questions. With all the work that goes into the quality of a bore, how could gunmakers not consider where it is pointing relative to the bore axis? I understand that Savage actually forgoes the use of lasers to straighten barrels, relying instead on experts to do it by hand. For these people to spend all this time on the straightness of the barrel without concern for where it is pointing boggles the mind. I’m sure the same could be said for the detail fanatics at Anschutz and any number of other makers.

    This is strange enough, but it is also not clear to me in which direction the bores deviate. I don’t understand how they could consistently point downward “relative to the line of sight of the scope that’s mounted on them.” Scopes are supposed to converge with the line of the bore at some distance in the usual sighting process, so their line of sight is designed to be adjustable. If the bore deviates down from the barrel axis so much that you cannot get the right elevation that is a problem. But if this is caused by accidentally drilling the bore at an angle to the axis, how come the deviation is always downward? Aren’t barrels screwed into place? As the product of accident, the orientation of the angle to the barrel axis–up, down, or sideways–should be completely random. So droop should indistinguishable from barrel deviation in all the other directions.

    Having such a consistent error as the process of chance and oversight in barrel manufacture is what I don’t get. Could it be that this is not entirely an oversight? I seem to remember a blog posting long ago that suggested that rifles were purposely designed with some droop. Perhaps with initial conditions of projectile power, scope size, optics, the offset distance of scopes required by the human frame, and a variety of other things, barrels were developed through trial and error with some droop to sight scopes at the usual distances. But perhaps increasing power and any number of other technological changes have evolved away from these standards so that what worked well before now shows up as a flaw. I would think that a fairly basic understanding of barrel manufacture–more than I have–could determine if droop was intentional or not.

    Matt61


    • Matt,

      Almost.

      “droop is not a curve but a straight line which deviates from the barrel axis”

      Not quite. Droop is the line of the bore (forget the barrel, because it doesn’t line up with the bore, or hole that’s drilled through it) that slants away from the SIGHT axis. In our case, the scope axis.

      B.B.


      • So, I am truly back to square one. So can this slant be curved rather than straight? If so, that seems awfully strange given the efforts to make barrels straight. Slanting away from the sight axis must mean down since the sight axis is above the bore. If this is done in error, why is the slanting always in the same direction instead of up and sideways as well. If it’s not an error, what is their purpose? Well, I have a high tolerance for not knowing the answer. 🙂

        By the way, thanks B.B. and FrankB for the advice about rust removal. FrankB, how did you know that I was rubbing away with my t-shirt for all I was worth? You warned me just in time.

        Matt61


        • Any curve in the barrel is irrelevant — “droop” applies to the vector as it leaves the muzzle.

          Now, the /trajectory/ of the projectile will be a curve — caused by gravity and air drag. Which actually contributes to the problem, since it means the projectile is always dropping away from the exit vector.

          The only time a sight line does not converge on the bore line is in some slow/heavy recoiling guns — where the recoil raises the bore line before the projectile exits.

          Laser bore-sighters rely upon projecting a beam on the bore vector — and adjusting the scope to intersect it, at some distance. Since that distance is usually moderately short, it partly compensates for the drop in the projectile at more normal distances. (basically, intersection at a short distance is aiming the bore “higher” than intended shooting distance)

          Oh, and for airguns, and some others, the barrels are NOT threaded and screwed into the receiver… They may just be an interference fit with a cross-pin to lock them in place (think shop vac tubes where friction on the tapered surface is it). On the Browning Challenger II (and likely the Buckmark) and High Standard pistols, the barrel is held on by a conical ended screw wedging it against the frame.


          • Baron W,

            Thank you for that info. That is good help. Notes were made of your stats.
            That is the type of things I was wanting to know.

            I like Buldawg’s comment on the welding tanks. Plus,…when I see a hand pump with 5 re-build kits included,…what’s that tell you about hand pumps.

            Thanks again,..outa here,…work early,….Chris


      • B.B.,

        Let me attempt to clarify your statement as best I can, please correct me if you believe I am wrong. Ideally, I believe that the bore of a barrel should be perfectly aligned to the center of the axis of the receiver. I also realize that this is impossible since in some AG designs, the barrel is located above the center line axis of the receiver but still should be perfectly parallel to it. Now, as an example, if the face/breech of the barrel, especially in the case of a break barrel is too long in relation the pivot point by even a few thousandths of an inch, you have barrel droop, where is your scope mounted, on the receiver. Now you have two options, use droop compensating mounts/rings or mount the scope on the barrel (very impractical), where most if not all break barrel rear sights are located, probably for that very reason.

        Bugbuster



  20. “The barrel isn’t actually drooping like a limp noodle — it’s simply pointed down and away from the scope’s line of sight.”

    Wouldn’t a barrel in parallel alignment with an optically centered scope’s line of sight qualify as a drooper? Since the barrel and scope’s line of sight are parallel, the bullet would never converge on the line of sight to permit them to intersect. The bullet would only drop away from the scope’s line of sight once it left the barrel, never rising to intersect with the line of sight.

    The barrel and the scope’s line of sight need to converge for the trajectory of the bullet to rise to the scope’s line of sight to be “on target”. It seems this lack of convergence is just more pronounced in airguns than firearms due to the relatively slow speed of the pellet and short target ranges of the airgun compared to the firearm.

    Tom


  21. Hello B.B.,

    The info on scopes is very useful. Thank you.

    I just happened to come across a good deal on a used RWS Diana 54 Air King .22 today. I have one, but this was in good condition and seemed to be priced right. It’s older than the one I picked up last year, and I think it may have the T05 trigger. How can I find out how old the rifle is, and if it is the T05 (or older) trigger? Also, do you recommend the UTG drooper mount for this one? https://www.pyramydair.com/s/a/UTG_Scope_Mount_Base_Fits_RWS_Diana_48_52_54_460_Magnum_with_TO5_Trigger_Compensates_for_Droop_Stops_Scope_Shift/2297

    Thank you!

    Jim M.


    • Jim M.,

      I’m not B.B. But I’ve owned a Diana 54. YES, I highly recommend the UTG adapter that you linked IF you have an older Diana 54 that these were made for.

      Serial numbers used to date these guns have become all but useless because so many folks have changed out the triggers to the T06. Here’s a link (and click on the multiple links within this links and realize many of these links are multiple pages) to help identify your trigger, understand the differences, shows how to adjust all 3 types. Recommend you pay special attention to what Scot Heath and Hector Medina have to say:

      http://www.network54.com/Forum/79537/thread/1318249791

      kevin


      • Kevin,

        I appreciate the link to that forum. The trigger on this older rifle could use some adjustment. It has a much heavier pull than the new 54 I purchased last year, one with the T06 trigger.

        I have the newer version of that UTG mount on the 54 I already have — it works great. Just wanted to make sure the mount I linked to will work on this older rifle. As I just replied to B.B. below, after he told me where to look for the date code, it’s stamped 08 94. I was surprised it’s that old, as it is in really good shape. It came with a Tasco scope and one piece mount on it that I want to replace. I have an extra UTG scope that I’ll put on it once I receive that drooper mount.

        Thanks!

        Jim M.



  22. Ref your final comment about cant, a high mount on a scope will show you your cant more clearly than a low one, but won’t be causal, in fact may be helpful in disciplining yourself out of it.
    In much the same way as high magnification doesn’t make you shake.


  23. Could droop be a scope issue?, a pellet falls a hell of a way compared to a firearm over a very short distance, I simply don’t seem to suffer from it…..not even on my Diana’s, however I don’t own a scope not made for air rifles by Nikko Sterling, is this, perhaps an issue in zero adjustability similar to the incorrect parallex focus issues when a firearm scope is fitted?. Ie a modified firearm scope that simply isn’t set up for 9″ drop at 30m despite having been recoil buffered and an altered focus lens.
    If you get the chance, perhaps try a Nikko scope on your worse drooper?


    • Dom,

      Droop is a real issue. A scope with a broader range of adjustment can compensate for some droop but not all in many airguns. Even the Nikko Sterling scopes.

      Not theory here but experience.

      kevin

      ps-I like some of the Nikko Sterling scopes.


  24. I’m not giving any particular shout out for Nikko, more puzzled why I haven’t ever experienced it in the fashion described, and the only conclusions I can come to is either it’s the scopes I use, which has been pretty consistant, or I’m immensely lucky, and boy!, that would be some luck, I started FT back in 1985 and have owned 50 or 60 spring guns in my time, maybe 20 of them with optics, I have had to shim the back of a scope once or twice, but mainly on pretty clapped out stuff, which is what I put it down to at the time.
    It certainly seems to be, somehow, less of a problem over here in the UK, certainly not a subject that really comes up at the airgun club…..and Nikko’s are on 2/3rds of the rifles you’ll see on these shores….just trying to figure it out.


    • Dom,

      You “let the cat out the bag”…..

      You guys are keeping all the straight shooters for yourselves and sending all the droopers accross the pond.

      😉 Chris



  25. Okay, I think everyone has gotten a little wrapped around the axle on this ‘drooper’ business. Perhaps a simpler way of illustrating the concept involved is to draw two horizontal and parallel lines. Top line represents line of sight, regardless of type of sight or scope employed. Bottom line represents the bore axis line and the theoretical path of the bullet’s flight in a vacuum. Extend the lines down range to infinity and the separation between the lines will remain constant, ie: the distance line of sight is above bore axis. Let’s assume line of sight through our scope is 2″ above the bore axis. All bullets/pellets, etc. will impact a target 2″ below the aim point.

    Reality is that we are not shooting in a vacuum and gravity is pulling the projectile earthward the instant it leaves the muzzle. We therefore need to replace our bottom line with a shallow arc to represent the projectile path. If we wish to have our line of sight correspond with one or two points on the arc down range, we need to angle the line of sight downward (or bore axis upward). We can adjust our line of sight to coincide with projectile strike on target at a desired distance, say 50 yards, for our shooting enjoyment. The projectile strike will be above or below aim point at distances other than the 50 yard ‘zero’.

    Hope this helps.


  26. >If the gun is, indeed, a drooper, you solve the problem during the mounting process. No need to take the scope off >and start over. If the gun isn’t a drooper, you just gained a lot of additional useful elevation adjustment.

    B.B., I completely agree and I might just use my ring/scope epoxy bedding technique on ALL my scope mounting projects from now on for this reason! Here’s an update on my future guest blog submission on the subject: I just received a UTG AO scope (front adjust) from Leapers customer service (great service, BTW). They confirmed the AO induced reticle shift I had found in the scope and corrected it. Now I have an unmounted and available scope to use for my guest blog demonstration and photos!

    On another project update, I purchased three new spools of “specialty” 3D printer filament–one kg each of polycarbonate, flexible polyurethane, and high impact strength PLA/acrylic. As with the PLA, ABS, and nylon materials I’ve used, these materials will bring new “learning curves” to be conquered, I’m sure!


  27. I hope it’s ok to ask this here, but I have a question about the cheaper UTG scopes. Long story short, I have a Benjamin Trail NP XL 725 .25 caliber. I bought it used and i think came with a Barska scope. I’m pretty sure the scope has given up the ghost. At the moment I’m kind of in a tight spot financially and I just want a scope that will take the recoil. I don’t care about the bells and whistles. Does anyone know if the cheaper UTG scopes like the Hunter ($40 at pyramyd) will stand up to the recoil for any length of time? Here is the scope I am thinking about.
    /s/a/UTG_4x32_Rifle_Scope_Mil_Dot_Reticle_1_4_MOA_1_Tube_3_8_Rings/3015


    • Captain Bravo,

      Welcome to the blog. You can ask anything you like on this blog. We don’t worry about the topic.

      The answer to your question is that red circle under the scope on the web page you linked to. TS stands for True Strength — Leapers (they make UTG) trademark for their design that’s braced in both directions.

      So, the answer is yes, that scope should withstand the recoil of your airgun.

      B.B.



  28. Hi B.B.

    I’m waiting for the ZR mount review.., but it’s not the case.

    Right now, I just want to throw in another topic to if/when you think it’s timely to consider.

    It’s about checking a scope’s internals health.

    Trying to solve the mystery about the culprit(s) of POI shifting, I always do an elimination process. Rifle? Me? Pellets? Scope?

    Well, even when I think the other usual suspects are not guilty at ‘this time’, I point my finger to the scope without being so sure. The reason is simple – several factors concurring at the same time to that lack of consistency.

    Suddenly, I think I’ve stumbled on a breakthrough, at least to my needs. I’m suspicious, as I never have read about it.

    Instead testing/analyzing through the POI deviations feedback, should I test the current scope’s capability to hold its ‘optical center’ after some recoils’ series? In this case, the POI itself doesn’t even matter, and you may isolate the scope as a single cause, no matter other possible causes, as rifle issues, shooter, pellet,.. The point is, even at its more comfortable internal circumstances (optical center), if the scope is not holding the erector tube position, we all know in advance the POI will shift.

    It seems so simple, but the problem is – am I missing something?

    Marcos


  29. B.B.

    Thank you for the quick answer. You’ve made me SO HAPPY !!!

    Btw, a good example when a ‘no’ is all you wish.

    Then, going on at my tightrope.., I’ll submit other ideas to you.

    To have the ‘optical center’ (OC) as a reliable referential in order to get reliable conclusions, it seems to me the most accurate way would be the ‘V box’ method. So, if possible with ‘that’ scope, we could start getting close through the ‘mirror’ method, simpler and faster, and do the fine tuning at the V box.

    Once trusting the OC, we could do other tests before the ‘recoils’, when we don’t even need a rifle.

    ‘Zoom test’ – if the scope has a variable zoom, we may change the power some times and check the OC at the V box.
    ‘Turrets test’ (and/or erector tube spring) – turn ‘X’ clicks to the right, X clicks to the left, and check the OC. Do the same with the elevation turret. Mix both turrets adjustments to have a ‘zero sum’, and check the OC.

    The scope tests series would be complete with the ‘recoils’.

    Regarding reliability, I think we have to upgrade the “usual” V box. Maybe an adjustable device to make company to our spring compressor? Maybe a kind of mount with open rings (high enough) we could apply over the spring compressor?

    B.B., by chance, would you have an improved “V box” device to (timely..) post a picture?

    Did I go too far?

    Marcos


  30. I’d like your opinion on my theory as to why so many scopes are destroyed by air gun recoil. I have a Leapers multi power scope I have installed on 3 heavy recoiling springers with no problems so far through 2000 rounds or so. All are/were droopers requiring special mounts.
    I have seen considerable reference to shimming but little as to numerical centering of adjustments. I have always felt uncomfortable shimming scopes so I have paid close attention to the drooper mount I use. I try to select a mount that allows the scope adjustments to get no closer to their end than 25% of their useful numerical travel.
    I believe leaving considerable travel on either side of the adjustment allows a protective cushion preventing breakage.
    What’s your opinion?


    • Facetjky,

      Welcome to the blog.

      Scopes are much stronger today than they were 30 years ago. Not nearly so many break from airgun recoil. Leapers build all their scopes to take the recoil of a spring gun.

      The return spring on the erector tube doesn’t protect much besides the erector tube. Lenses can still pop loose and break.

      I do think your attention to keeping the adjustments in the middle of their travel helps your scopes, though maybe not as much as you think.

      B.B.


  31. Thanks for the quick reply to the drooper question I have had for years.
    I have another problem that has developed as I try to shoot straight with a springer. I am having consistency trouble with that multi power Leapers on an Airking. All appears Ok except I hit all around the bull. The scope is a bit high preventing a good cheek weld making it possible for my eye position to wander. Experimenting I find the POI moving all over when I look through the scope from afar i.e few inches extra. Is cheek weld that important or is something loose inside the scope? I thought this “parallax” problem was taken care of with scope design.


  32. I got an RWS 460 Magnum .22 and an RWS 34 .177 over the summer. Both have a lot of barrel droop … on the order of about 13.5″ at 20 yards (that works out to about 21″ at 30 yards, a number I’ve seen repeated in many places). Using Leapers compensation mounts for RWS guns with T06 triggers, I was able to take care of about half of the droop. Both guns still needed more.

    I was watching a video by Rick Eutsler a couple of months ago where he was discussing homemade scope shims. He made a shim out of a few thicknesses of a soda (or beer) can sandwiched between electrical tape. I decided to give it a try. I made two shims with five thicknesses of soda can with the tape on each side. They are about 1/4″ wide and slightly longer. I then placed one in between the rear of each of the scope bases and mounts, not between the rear scope ring and the mount or in the curved section of the rear scope ring.

    Presto, that eliminated the droop problem. The scope adjustments were easily within range of both scopes and there was no danger of damaging the scope tube. The shims were thin enough that there was no problem with the mount bases and mounts clamping each other so that they stayed put.

    I hope this helped.


  33. Here is a slightly more detailed description of making the shim.

    Most of the shims addressed above talk about shimming within the curvature of one of the rings (mostly the rear one), immediately under the ring or reversing the rings. There is another way that will correct up to about 13.5″ of droop at 20 yards without damaging the scope tube.

    First, get the Leapers droop compensation rail mount (MNT-DNT06) designed for RWS droopers. It’s also useful on other makes of rifles. This will take care of about 6.5″ of droop at 20 yards. If you need more correction, read on.

    For the shim, you will need one empty soda or beer can (rinsed and dried), tin shears, a hammer, some electrical tape and a razor blade.

    Cut a 1/4″ wide by 2 1/2″ long piece of tin. Trim the edges. Start folding in 3/8″ lengths. After each fold, tap the shim with the hammer to smooth it out. Continue until you have six layers of tin. Cut off any extra tin and trim the edges. Get a piece of tape about 2″ long. Lay the shim on 1/2 of the tape and fold the tape over like an omelet and give the shim a few more taps with the hammer. Trim the excess tape. This shim measures about .0425 inches (or slightly more than 1mm) thick and will compensate for another 6′ of droop. If you need less correction, decrease the number of layers of tin.

    The shim is now ready to install. The key is to place the shim between the barrel (or scope base) and the compensation rail mount. If the scope base doesn’t have a flat area in the rear so that the shim doesn’t move around when installing it you may have to use something like a bit of blue LocTite to hold it in place. Once the shim is installed between the scope base and the rail mount and tightened down, you can install your scope normally on the rail mount.

    One more thing. If you need to move the point of impact down, just put the shim under the front of the rail mount.


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