by B. B. Pelletier
In this report, I’ll tell you about shooting field target using the holdover method and the scopes that go with that. I held over for the first three seasons I shot field target. The first season consisted of a couple demonstration matches to shake out the bugs in our club. We had to do everything for the first time, and we were using 20 borrowed targets that were somewhat obsolete by the time we got them. There were all sorts of operational issues.
It all started at the beginning
I had reluctantly agreed to be the match director because, of the four men who founded the Damascus Ikes Field Target Association (DIFTA) club, I was the only one who had competed in field target matches before. Truth be told, the matches I had competed in would be called Hunter Class today because nobody sat to shoot. One of that club’s founders had a bad back, and they just ran the thing as a stand-up competition. I tried to sit to shoot just once, but gave up after all the criticism and catcalls. I missed the shot, too!
So, for the first match at DIFTA I was sitting in the American Airgun Field Target Association (AAFTA) approved position for the first time. I had a rulebook in my pocket and dreaded the moment that some lawyer would pop out of the crowd to challenge a ruling I might have to make, but it never happened. I didn’t have to make any rulings for several matches, by which time I had sort of figured things out. Sort of.
And I was a holdeover piggie! That’s really not a field target term–I just made it up in the last report. But it certainly illustrates the level of informality that accompanies those who hold over instead of adjusting the reticle for every shot. I’ve already addressed what it takes to adjust for every shot. Now let me tell you what you have to do to hold over.
What does holdover mean?
If you decide not to adjust the scope for every shot, the other alternative is to aim in different places to compensate for the trajectory of the pellet. A gun that hits the point of aim at 20 yards will not also hit there at 40 yards. You’ll need to aim differently to compensate for where the pellet will strike the target. This is called “holdover,” though sometimes you’re holding under, instead. It all depends on how you sight-in your scope. I’ll explain as I go, so don’t hurt your head if this isn’t clear yet.
My first FT gun was simple
Being match director, I wanted to shoot a gun that was lightweight and easy to use, because I was running all over the course keeping the match going. Targets were fouling and questions needed answering and I didn’t want to also have some technical challenge to deal with when I sat down to shoot. So I put a Bushnell 6-18x Trophy scope on top of an FWB 124 and I was set. I sighted-in the gun for the first point of intersection at 20 yards, which meant that it was more or less on target out to 30 yards and shooting low at all other ranges. With the gun shooting 860 f.p.s., a 20-yard zero gives the largest flat spot that’s possible in the trajectory.
I could have done something radical–like sighting-in for 15 yards. Had I done that, the gun would have shot low some of the time and high some of the time. That would have been a rifle that had to be held UNDER, as well as over. But I didn’t do that, because it’s too confusing.
From 10 yards to 19 yards, my rifle shot low, but got progressively higher as it approached 20 yards. Then, between 20 and 30 yards, it was hitting where the crosshairs were, more or less. The truth was actually a little different than that, but let me address that in a moment.
Beyond 30 yards, the pellet began to hit lower than the aimpoint, again. So for all shots closer than 20 yards or farther than 30 yards, I was hitting low. I had to hold the intersection of crosshairs above the place I wanted the pellet to go. I had to hold over. Holdover!
Yes, but HOW MUCH over?
I sighted-in my rifle on the sight-in range on a quiet day. The distances to targets on that range were already marked off from the firing line. I first marked the actual parallax (focus) ranges on white tape I put around the objective bell of the scope. And then I learned how much I had to hold the crosshairs over those targets at the distances mentioned above. At 10 yards, for instance, the pellet was hitting a full inch below the crosshair intersection, while at 19 yards it was only hitting about one pellet-diameter below the intersection. At 40 yards it was hitting an inch below the crosshairs again, but I discovered a funny thing.
One inch at 10 yards looks a lot different than one inch at 40 yards! Or, put another way, one inch at 40 yards is very small, while one inch at 10 yards is huge–through an 18x scope.
I guess so
Oh-my-gosh! As distance increases, the images in the telescope get smaller, so the aimpoints are not regularly spaced inside the scope! You have to, gulp, GUESS!
Call it estimation if you want to sound learned, or interpolation if you think you’re a scientist, it’s still a SWAG [Scientific Wildly Assumed Guess]. Before your first 60 shots are downrange, you’ve learned that holding over is an imprecise practice at the very best. Some shooters do better with it than others. I was eventually able to get up to the 2/3 level, where I remained with a lot of other holdover piggies. Two-thirds means that in a 60-shot match, I’ll shoot a 40. On a great day–it’ll be a 44; on a lousy day–a 35, but that’s where I’ll stay.
When I was holding over, you could have told me the exact range to each target in millimeters and stopped all wind for every shot–it wouldn’t have made any difference. But I had lots of fun and met some nice people.
In my scope, there’s a duplex reticle. Four fat lines become skinny in the center of the scope. By using the places where they go from fat to skinny as aimpoints, I picked up four more aimpoints. If I had a scope with a mil dot reticle I could have used those dots and even the spaces in between them as additional aim points. But you know what–it doesn’t make much difference. Because one inch at 47 yards looks different than one inch at 13 yards. And your pellet will drop about an inch between 47 and 51 yards (max distance is now 55 yards, remember?).
The duplex reticle has 5 aimpoints–the center intersection and the 4 places where the reticle wire thins.
But that’s not all. The freakin’ pellet also doesn’t stay on the vertical crosshair as it goes away from the gun! From 10 yards to 20, it’s on the right side of vertical; from 30 yards to 55, it’s on the left. I need to aim to one side or the other, depending on the range. Oh, it isn’t that much, but you don’t have to be off by much to hit the side of a 3/8″ kill zone at 12 yards. And you remember what touching the side of the kill zone can do.
So, I did what every other holdover piggie does. Somewhere on the butt of their rifle will be a white card with lots of numbers. Or they will have the card in their pocket. Or it’s on a chain around their neck. (That’s how you spot them at a match.) It has notes like this:
40 yards – one inch over and half a reticle-width to the left.
45 yards – 1.5 inches over and one reticle-width to the left.
50 yards – 2.5 inches over and two reticle lines to the left.
The language may differ on the notes. They may talk in terms of dots instead of inches or lines, but it all means the same thing. This guy isn’t going to win the match.
Want to know why? Where on those notes above do you see 47 yards? It isn’t there. Why?
Because a 6-18x scope stops working for rangefinding at about 30 yards. So somebody using a scope like that as a rangefinder can’t tell how far the target is anyway, so what use does he have for precise aiming references?
It’s all a SWAG, and it doesn’t take 30 shots before it sinks in.
“Why, B.B., it almost sounds like you’re saying that holding over isn’t a good way to shoot a field target match.”
Oh, it does, does it? Well, let me make it clear.
HOLDING OVER ISN’T A GOOD WAY TO SHOOT A FIELD TARGET MATCH–unless you don’t care about winning.
It was a GREAT way for me to shoot matches for over two years, because I didn’t go to win. I went to shoot. To experience the fun of the course. And my job was to make sure the matches were fun and fair for everybody else.
In year three, I started shooting a PCP, and I mounted a 8-40×56 scope that was optically centered and ranged for every yard from beginning to end. My scores jumped up to 46-49, with 51 being a really good day. A lousy day would be a 44.
Did I have more fun? No. But I did have different experiences.
So, how do I move from 48 to 60 points? I drop 100 lbs., learn to gauge wind, sort all match pellets (though I was doing that at the end), buy a sitting harness and learn to use it and pay more than $300 for a scope. Oh, and PRACTICE!
What I DON’T have to do is buy a more expensive rifle, buy a carbon fiber air tank or spend $500 for a custom scope mount (yes, I really saw that). Money doesn’t win field target matches, despite what the losers say. What wins is determination. You have to really want it.
Holding over is a good way to get into field target on a budget. And whenever someone asks me this question, I know that’s what he’s going to do: “B.B., what scope costing under $150 do you recommend for field target?” I will make a recommendation to that guy. And he will be able to shoot field target–by holding over.
Just as long as you all understand that this guy is just like me–out for a good time and no hopes of winning. Or maybe a hope–just not much of a chance. He might as well ask, “What American pickup truck can I buy for under $20,000 that I can also use as a dragster?”
Holding over will get you in the game, but adjusting for every shot is what it takes to win.
My suggestion for FT beginners is to zero the gun at, say, 25yds about 3/8″ high. Shoot dead on for all shots from about 15 to 40yds. For any closer or farther, aim for the top of the kill zone. If it is windy, aim for the windward side of the kill zone. If the first shot misses, aim that much higher/lower (or left/right if windy) by the amount of the miss.
This still requires that one be a good marksman — a step that many assume comes from the equipment rather than the shooter. Still, this approach should get you about 75% or better on a typical FT course if you are a good marksman!
B.B. please point me to the blog about how to optically center a scope. From SavageSam
B.B.,
I really like this series of articles. Even though I have never had the opportunity to shoot FT these articles are critical for those of us that want to improve our groups at multiple distances and/or hunt small pests.
The common thread in all three parts is get to know what your scope and gun will do at different distances. In an effort to control small pests last summer with my air rifle I shot at 10 yard increments up to 30 yards then shot at 5 yard increments from 30 yards to a maximum of 50 yards since I’m not a good enough shot to shoot my pellet rifle beyond 50 yards. You’ve taught me that I need to put more effort into learning what my gun will do at even smaller increments of distances. My ignorance in not realizing that even small changes in distance that i overlooked are partially to blame for my misses/change in poi. I’ll take the rest of the blame for shooter error. Although I took the time to optically center my scope I also found that my poi doesn’t stay on the vertical crosshair at some ranges. I remember an article you wrote a long time ago that said you no longer optically center your scopes but you did it when you shot FT. In your initial years of shooting FT that you’re talking about in today’s article was your scope optically centered?
I must assume that when you began shooting FT with your 6-18x Bushnell Trophy on the FWB 124 that you dialed your scope for one magnification (18x?) and left it there for the entire match thereby eliminating another variable on your “range card”?
Great article that applies to all of us airgunners that get bored shooting at the same distance but still want the knowledge to get good groups at a variety of distances.
kevin
/blog/2005/7/how-to-optically-center-a-scope/
Everyone,
Re: Spring guns 101
Had an interesting experience last night that reinforced not one but three basic lessons from B.B. about what to do when a spring guns accuracy falls off.
Some of you may remember the two scoped B-26’s I gave to twin boys at the beginning of January as birthday presents (many thanks to Mike Melick and Wayne “Wacky Wayne” Burns for their efforts that made this possible). In addition to the scoped guns I gave each boy a tin of .22 caliber RWS Superdome pellets (500 count) since these were overwhelming the most accurate pellets reported in these guns and my limited shooting of these guns after mounting the scopes and sighting them in proved that the superdomes could group well.
I’ve been thrilled with the reports on how well received these gifts were. I’m proud of these boys since the reports (even from their parents) were that they are shooting safely and accurately (and often). These boys could even be seen hiking through two feet of snow to shoot the squirrels off their parents fruit trees since the squirrels girdle the branches this time of year. The tins of pellets lasted about one week. I’m convinced that they would have over 3,000 shots on these guns if they wouldn’t have been forced to wait a week for replacement pellets.
On Monday evening I got the call. One of the guns was still shooting strong but he “couldn’t hit the broadside of a barn” with it. I asked if he was using the artillery hold and in a fit of frustration he said that even his brother couldn’t hit anything with this “inaccurate” gun and they’re both using the light hold.
They came over to my home last night with both guns and shot them at a 20 yard target I have set up. Sure enough one of the guns was still grouping and the other couldn’t shoot a 5 shot group less than 4 inches! There were 3 problems that turned this sad and frustrated lad into a very happy and proud airgun owner once again (Thanks B.B.).
The first thing I did was tighten all the screws. Stock screws were very loose. Mount screws and scope ring screws were still snug (thanks blue locktite). Groups got a little smaller. Next I cleaned the barrel (you know the B.B. drill..brass brush, jb bore paste, etc). I haven’t ever heard of this but superdomes fouled this barrel considerably. Chunks of lead came out. Groups shrunk to approximately one inch and even I couldn’t get them smaller. We started trying different pellets. In this gun the Air Arms Diablo Field .22 caliber pellets shot a group where all 5 pellets touched. Eureka!! Happy kid.
Spring gun 101 per B.B. Tightened screws, cleaned barrel and re-selected the best pellet.
Now I need to find this kid the Air Arms Diablo Field .22 caliber pellets since Pyramyd AIR has discontinued them. Anyone?
kevin
PS-Yes, I also had to clean his brothers gun since he didn’t want to be outshot by his sibling.
Kevin,
No, the scope mentioned above has never been optically centered. Back then I didn’t put no stock in all them fancy-Dan high-fallutin’ things all the winners were doing to their equipment. When I moved over to PCPs, though, I started doing many of them and discovered they really work!
B.B.
BB
A great article! I have never shot field target but I can appreciate what you say about enjoying the sport. Calculating every shot would rob all the fun for me. I just get a rush when I score a hit from estimation (not interpolation!).
Ton
In regards to Kevin’s post. I know b.b. has said that cleaning isn’t all that necessary in low powered airguns. At the moment mine are all below 500fps (Avanti 853, Gamo Compact and Walther CP99). But being that I always want to do my bit for the faltering economy (spend money) will it help at all to purchase a cleaning kit for these guns…or should I just spend the money on more pellets.
CowBoyStar Dad
CowBoyStar Dad,
If your accuracy hasn’t diminished you don’t need to clean the barrel. If it has, you don’t need a cleaning kit you just need a dewey rod in appropriate caliber (they come with a jag), a brass brush and some jb bore paste. You can cut up an old t-shirt for patches. B.B. uses tetra gun lube at the end I use ballistol for a thin film on the inside of the bore. Kits have a lot of extraneous stuff that you pay for.
kevin
B.B.
As Kevin said, these articles are very much appreciated even by those who do not shoot field target. Some questions and observations. Shooting a match and directing it seems to me to be extraordinarily difficult. I gather that one must use holdover to compensate for wind, and if that’s the case, it seems like the effect of zeroing for all distances would be considerably blunted unless you are in dead calm conditions. I don’t see how holding over affects budget; isn’t the difference the price of a sidewheel and a scope that can handle it? These can be expensive but significantly less than the price of guns.
And, vindication for Dr. G! I wrote earlier that I was skeptical that pellet spiraling would cause the point of aim to move in a circular fashion as distance is increased as he claimed, but I suggested that one experiment to verify this was to see if field target shooters adjusted for windage as well as distance with their pre-set zeros. And I think I finished by saying that if this were the case, we would have heard about it by now. Well, I guess we have. And as for the reason why, I guess the pellet spiraling is the best candidate I can think of.
Matt61
Regarding last night’s discussion, optically centering a scope is not the same thing as sighting it in, right? I gather that optically centering is aligning the crosshairs with the axis of the scope, and sighting the scope is adjusting the crosshairs so that the pellet trajectory meets the target at the point of aim at a given distance. In most cases this will not be the same setting as the optical center.
If this is all true, why do you need to bother with optically centering the scope since the goal is to get it sighted in? I don’t see how the optical centering contributes anything.
Matt61
Kevin
Make sure that you read all the comments and try the mirror method I described there.
Revwarnut
Matt,
Holdover is to compensate for the trajectory of the pellet. It falls 4-6 inches over 55 yards.
The winds presents even more problems.
The comment about scope cost was that low-cost scopes don’t have the necessary features (power, mostly) and clarity to rangefind out to 55 yards. Hence they are inadequate for adjusting and must be used for holdover. The presence of a sidewheel doesn’t make a field target scope by itself. The optics have to be there first.
Optically centering the scope is not the same as sighting-in. What is does do is ensure the pellet stays on the vertical reticle at all distances, so it is related to sight-in, just not the same thing.
Without an optically centered scope, the pellet wanders from one side of the reticle to the other, depending on the range.
B.B.
I am sure BB can add to this, but one advantage of optically centering a scope (which is done BEFORE mounting it on the gun)is that you can be sure you are starting from a true zero point from true center of the scope.
The ideal adjustment on a scope would be one where the crosshairs are always dead center of the physical lenses. That is what optically centering a scope does for you. It sets the crosshairs at that spot so you can see how far off it is once mounted. Your scope mount may cause a skew in the aimpoint just from the way it holds the scope for example.
This would allow you to adjust some of the aimpoint of the scope using an adjustable mount before adjusting the crosshairs to get the scope as much on target as possible.
Ideally, any further adjustments should then be minimal using only the crosshairs and the scopes accuracy will be improved because the scopes internal parallax error will be at minimum.
The least accurate adjustment of a scope would be one that you had to crank over to the maximum one way or the other, because then the internal springs are not applying equal pressure on either side of the adjustment since one is at max compression and the other is at max relaxation. In this condition, many scopes will actually change aimpoint just from normal handling.
BB,
I agree completely that meticulous calibration of scope, big sidewheels, harness, and tons of practice are necessary to be a top FT competitor — it just doesn’t sound like fun. How popular is the Hunter class? It seems to me that would attract a lot more people.
BG_Farmer,
The Hunter class is very popular for the reason you mention.
B.B.
Revwarnut,
I read all the comments. Last summer I was nuts about keeping pellets on the vertical reticle at all distances. Never could get the “mirror trick” to work in optically centering my scope. Even bought a thicker mirror at a thrift store but couldn’t get enough light in the scope to make adjustments. I used an old set of rings mounted on a piece of plywood vs. cutting two notches in a cardboard box and optically centered my scopes. Took awhile but now it’s not too difficult. My problem has been in finding a decent set of adjustable rings (terrible luck with the current quality of b-square adjustables) since once your scope is optically centered you should never touch the windage adjustment again. If I could find a good set of adjustables (other than b-aquare or burris) I would probably be interested in the exercise again. Now I make a note on where the pellet is off vertical and just compensate with changing poa. Our seemingly nonstop wind also minimizes the importance of an optically centered scope since I need to adjust the poa anyway.
kevin
Kevin,
Re: Spring guns 101
I wonder if the reason chunks of lead came out is because the barrel had rough spots inside?
.22 multi-shot
.22 multi-shot,
Maybe but I doubt it. The superdomes have that strange scoring on the outside of the skirt. One piece came out large enough to see what looked like the superdome scoring. Could have been a piece of another pellet with rifling marks from the barrel but I doubt it. Anything’s possible but scrubbing that fouling out of the barrel cured it.
kevin
Kevin,
If the boys are having trouble with fouling, should they lube the pellets?
Herb
Hi guys, is it safe to assume a new scope, and I’m really only asking about Leaper’s here, is optically centered out of the box?
-Aaron
Aaron,
It is almost 100 percent impossible that a new scope is optically centered. Any more than your new car comes with a radio preprogrammed to your favorite stations.
B.B.
Aaron,
ass-u-me = ASS out of U & ME
No…If you're going to use an optically centered scope, that means that you're going to use an adjustable mount. If you're going to all the trouble to use an adjustable mount, then spend a few minutes first to double check scope to verify that it is optically centered before you start fiddling with mount.
Herb
Field Target shooters –
Do you adjust magnification power on scope as distance of shot changes, or do you leave the magnification cranked up for all the shots?
Herb
B.B.
Thanks. Good heavens, I better get out there and optically center my scope. Keeping pellets on the vertical crosswire sounds like a very good reason to do this. It also may be another source of the side-to-side movement that Dr. G was talking about.
Herb, an adjustable mount would make sense in conjunction with the optical centering, but my impression is that adjustable mounts have their own problems. Centering the trajectory in the vertical sounds like a good reason for optical centering even if you adjusted the scope itself which would introduce some vertical parallax.
Matt61
Matt,
Somewhat confused by your comment “… an adjustable mount would make sense in conjunction with the optical centering, but my impression is that adjustable mounts have their own problems.”
If you don’t use adjustable mounts, how would you possibly use an optically centered scope?
There has been much discussion about “optical centering” without too much discussion on what else it takes to make it useful. After you get scope optically centered, then you need to adjust the mount(s) (somehow…) so that the POA coincides with the POI at say 20 yards. Now fine click adjustments for elevation and windage won’t too greatly effect the scope optics.
I guess you could play with shims, but there would be limited adjustability. Grinding the mounts to fit would be very difficult. A machine shop could make a set of custom mounts, but that would be very expensive.
I’m just getting ready to use adjustable mounts to try this for one scope and I’m expecting it to be somewhat painful. But I don’t have access to a machine shop to custom trim the mounts. I think you’d still have to use an adjustable mount of some sort to get the measurements needed.
Herb
“I’m just getting ready to use adjustable mounts to try this for one scope and I’m expecting it to be somewhat painful.”
Herb,
Before you start fiddling with the mount, say a simple prayer of intent to God/your higher self: “Surprise and delight me”. Then it should go much easier.
Herb
Last night you asked about testing the my 2200 at 8; 9 and 10 pumps. This is what I came up with.
As a side not my garage was 50 degrees today instead of yesterday’s 44.
14.5 gr. RWS SuperDomes:
10 pumps 570 FPS (yesterday it was 565 FPS)
9 Pumps 558 FPS with an extream spread of 2.5 fps
8 Pumps 537 FPS
Intresting that we were a bit faster today in only a 6 degrees rise in temp. I alos point out the ES of 2.5 FPS on 9 pumps because that was my low. 10 pumps had a 3.1 ES; and 8 pumps had a higher 6.3 FPS.
Another note: When I finished the brain storm hit to oil the pump felt a bit with some pelgun oil. This gave an increase of 9 FPs. 10 Pumps were now giving an average of 579 FPS.
JoeG from Jersey
BB and Anon.
Here are some velocities from my Remington AM 77. These velocities were recorded back in September. (Warm Garage) 10 pumps 5 shot strings.
7.9 gr, Crosman Premier = 753 FPS
7.7 gr Beeman Laser Sport = 720 FPS
10.5 gr. Beeman Kodiak = 644 FPS
I retested the CPL’s tonight in the cold garage and they tested out a 717 FPS.
So it seems that the colder weather could be effecting the Velocity on the PSP rifles. I guess time will tell.
JoeG From Jersey
Matt 61,
You and I think alike. With all of Dr. G.’s comments about poi shift at different distances I couldn’t help but think a better cheek weld and/or optically centered scope would minimize the shift.
Herb,
You are right. If you’re going to go to the trouble to optically center a scope you need adjustable mounts or some other method to move your windage poa to poi. Per B.B. any adjustments for windage after optically centering a scope will undermine what you have done. Adjusting for elevation is ok but you never touch the windage adjustment after optically centering a scope.
kevin
JoeG
Thanks for the 2200 measurements!!
Really interesting that your rifle keeps going up for 8, 9 and 10 pumps. Sort of makes sense to me that the extreme spread goes down as the number of pumps goes up. Instead of 10 pumps think of it as 9.87 pumps – Don’t quite get a “full” pump sometimes. Also the pump has an upper limit for the pressure that it can create since it is a one-stage pump. So you can’t put more pressure than that into the gun. Also 8-9 pumps has an increase of 21 fps, but 9-10 pumps is 12 fps. Saw exactly this sort of drop between number of pumps with my Daisy 22SG.
Curious that BB’s rifle seemed to go down in velocity from 9 to 10 pumps. Wonder if the decrease is real or an anomaly.
Herb
Herb
If I get some time on Thursday or Friday I will test my 22SG and Daisy 881 and maybe the Sheridan as well. I’m intrested to see if the possible colder weather works the same with those.
I guess I should test a springer as well.
As far as the velocity gain per pump goes, its reported that way as well in James Houses book.
JoeG from Jersey
RE: 22SG & Pumps
Went looking for my data for JSP Exact Express pellets with my Daisy 22SG
Pumps FPS (average of 5)
3……312
……….delta 107
6……419
……….delta 56
9……475
……….delta 27
12…..502
……….delta 14
15…..516
40…..540 (1 shot…)
With 40 pumps air was noticeably leaking out when pumping. I was trying to determine what the maximum would be.
Herb
B.B.
Thanks for the report on field target scopes.. I guess I’m a holdover piggie in transition..
It IS a lot of work to have any chance of a competitive score… but that can be the fun part too.. if one keeps a less serious attitude about it.. I’m just trying to keep improving my shooting little by little..
I’m now practicing more going from 12 yards to 30, to 55 yards.. and learning the adjustments necessary, instead of doing so much practice at one distance indoors at night only.. the indoors is good for trigger timing and steadiness practice, but the other is just as.. or more important, I’m now finding..
And this blog was a big help!! thanks!!
Wayne,
Ashland Air Rifle Range
Herb,
My understanding from B.B.’s response is that optical centering without adjustable mounts will allow you to keep your pellet on the vertical crosshair as you adjust for distance, so you eliminate one half of the error of parallax. That is all to the good, but it occurs to me that once you adjust for windage (as Kevin noted) your optical centering goes out the window unless you keep some very meticulous record of your clicks, not likely or worthwhile.
Using adjustable mounts would seem to help, but if such a mount is really so limited that you will need to make fine adjustments with the scope anyway, it doesn’t seem all that helpful.
So, it seems to me that the optical centering is about in the category of sorting and lubing pellets. It might make a difference at the highest level, but otherwise it is useful mostly as a starting point. In the course of shooting, it will be heavily compromised by windage and elevation adjustments and by even slight movements of the face on the stock.
Matt61
Matt,
Optical centering isn’t the magic silver bullet. But if you center the scope off the rifle, then the only way to align the vertical crosshair with the pellet’s path is to mechanically adjust the position of the scope on the rifle, eg adjustable rings.
I’m forced to adjustable rings due to an error in cutting the dovetail in my favorite rifle, the 22SG. I figured that as long as I have to play with adjustable rings, I might as well start with optically centering the scope.
Think of it this way. Ever looked at the edge of a magnifying glass? the image isn’t as clear on the edge as it is in the center. Also around the edge the image is distorted. Optically centering the scope basically moves the image back into the center of the magnifying area where the image is the clearest and the least distorted.
If you’re trying to range find by adjusting the AO you need to tweak every bit of precision that you can out of the scope.
Herb
Matt,
I think there’s more than one thing being discussed: 1) optical centering of the scope; 2) “perfect” alignment of the scope with the bore. Optical centering is the ideal, but the less movement in windage and elevation necessary at the sight-in range the better, so that minor adjustments during sight-in do not force the spring-tensioned inner-tube mechanism towards the end of its travels. Aligning the scope with the bore is even more essential, otherwise, you’ll shoot on one side of the POA at close ranges and the other past the sight-in point. Many rifles that are shot at “the range” can have that problem, and their owners may not know it. For any kind of hunting or multi-range use, its unacceptable. That’s why its necessary to swap rings, lap rings, use adjustable rings, or whatever else is necessary to make sure scope and bore are properly aligned, particularly in regards to windage. Yes, you vary from the ideal when you make adjustments at sight-in or range corrections, but the overall situation is much better.
PS. Herb, you were typing at the same time as I:).
Yesterday,I was shooting the Whisper at the range. After some warm up and sighting shots, I got a 5 shot, 0.75-inch group at 50 yds. Temperature was about 48F.
From then on, it got really bad. I retightened all stock screws, which helped with grouping size. However, pellets were hitting about 3 inches low and 1 inch to the left. Wind was not an issue. Temperature dropped to about 33F in about half hour.
Is temperature effect on scope potentially repsonsible for this? or just my frozen fingers? Speculation is fine…
Thank you
Great discussion guys!!
Thanks for working it so hard, it takes that for me to get it!!
Wayne
Tunnel Engineer,
Re: Speculation on your moving poi
Yes temperature can affect your scope. If the gun came from inside the house to the outside where temperature dipped to 33 degrees in 30 minutes that could explain some of your point of impact shift. Don’t think it could account for all of the 3″ low 1″ left though. That’s alot. More than I’ve experienced in some dramatic temperature change. If a 5 shot group all landed 3″ low and 1″ left I don’t think we can blame this group on you.
Do you have locks on your scope adjustments that could have been loose? Did you tighten all screws including the trigger guard screws and pivot bolt screws? Did you overtighten? Did you take the scope off and shoot with the iron sights? Pure speculation.
kevin
Need help from any Gamo Whisper owners out there…!
The issue I had yesterday trying to sight the scope seems to be due to the scope pin plowing into the scope rail… I believe the rail is made of aluminum (and not structural aluminum for that matter), and cannot handle the bearing or contact pressure imposed by the scope pin during firing. This happened even though I tightened the side Torx screws
The pin elongated the hole by about 1/8 inch and, worst of all, the pin started “riding” the deformed material of the rail.
I think I saw a comment about this happening to someone else on the internet. What can I do to fix this? Can I find a better replacement rail? maybe made of steel? Is this an almost necessary design flaw or what is the matter?
And yes… the 2 inch shift I got yesterday was not temperature.
Thank you
I have a rws 34 (.177) and am wondering which type/brand I should use for field target shooting.
George,
What price range for a scope are you wanting to stay within?
kevin
George,
Try Crosman Premier 7.9-grain pellets and JSB Exact 8.4-grain pellets.
B.B.
Thanks.
BB ,,, or anyone that can help.
I recently bought a rws 460 magnum .22 with a leapers 3-12x 44 scope.
I am unable to shoot past 35 feet for the next 2 weeks. and that is the range im using now.
my crossman premiers can hit a dime every time at 35′.
but all other pellets are off by quite a bit.
crow magnums are the worst but rws super domes, rws super h points, predator polymags, and beemans field target specials are also off. they usually shoot high and to the right compared to CPs.
i think I have red most of the scope posts and understand the importance of a loose hold. I use a gun rest as well.
I would like to use 1 type of pellet for targets and another for hunting in the future.
what do I do from here?
thanks guys.
DOUG C
DOUG C,
I also have a leapers 3-12X44 full size swat scope. Good scope for the money.
The crosman premiers are a good hunting pellet. With the exception of the crow magnums (that don’t group for you, so don’t use them) the other pellets you mentioned don’t have as good ft lb energy over range. If the crosman premiers give a good group hunt with them. Remember to lube the crosman premiers since they can lead a barrel in a strong springer like a RWS 460. If you don’t lube your pellets search “whiscombe honey” on this blog.
For target shooting, if you find a pellet that can group better than a dime at 35 yards use that instead of the crosman premiers. Just realize that you will probably have to re-adjust your scope for the different pellet since it will probably have a different flight characteristic than the crosman premiers and will have a different point of impacet (poi).
kevin
kevin
thanks
i have a #$%% load of all these other pellets, i guess ill have to use.
I will try the cp’s for hunting, and yes I oil them.
i mean 35 feet not yards.
thanks again kevin
DOUG C
DOUG C,
My fault. I misread your comment as 35 yards not 35 feet.
If none of those other pellets do well in your other guns you may want to consider selling or trading them on the yellow:
http://www.network54.com/Forum/79574/
Listing them on the same ad with separate prices for each and then a discounted price for all of them together seems to work well for others that were in your same situation. Not that uncommon. We all try different pellets and end up with many tins of pellets that don’t work. They work in other guns though.
You may want to try JSB pellets (both the exacts and jumbo’s). They worked well in a high powered .22 caliber RWS I had as did the crosman premiers.
kevin
does anyone know which pistol from umarex is quietest:colt 1911, beretta 92fs, walther cp88, or desert eagle? my brother has a s&w 586 8-in. barrel and it is pretty loud. Pyramidair states on the specs of the walther cp88 that it is 4 med-high on the loudness scale putting it above the beretta and colt which are 3's.
Are their optional compensators helpful in terms of improving velocity and accuracy? A customer service employee from pyramidair said they were.
Is the beretta xx-treme worth the extra money over the walther nighthawk? I have read many great reviews of both but some say that the nighthawk is toy like – something that i do not want. will they both shoot accurate out to 20-25 yards?
Anyone with any luck taping the beretta mock silencer to make it silenced. B.B. said that it does little to reduce noise.
Thanks
R7-dude