Precharged pneumatics, regulators and power adjusters: Part 1

by Tom Gaylord
Writing as B.B. Pelletier

This report covers:

    • Two things
    • What is an air regulator and what does it do?
    • How does the valve behave?
    • So — why have regulators?
    • Result
    • Why you need a chronograph
    • What I have not yet addressed

Today’s blog was a gift from reader Michael, with several others joining the discussion. Here’s what Michael said last Thursday.

B.B.,
I’m not a future TexanSS owner, but I enjoy reading about any model of AirForce air gun. I have considered buying a TalonSS ever since AirForce came out with them, and I’ll keep thinking about one until I someday break down and get one.

They are accurate, lightweight, cool looking, etc., but to me the greatest appeal is AirForce’s wide ranging power adjustment. To me that is huge. Want to increase shots-per-fill for target practice? Dial it down. Want to rid your side yard of that pesky squirrel but you have a .25 Condor? Dial it down to squirrel power.

But too many of the PCPs hitting the market these days lack an easy to use power adjuster. Why is that? Is it difficult to implement in a design? An expensive-to-provide feature?

Michael

My answer was as follows.

Michael,
Wow! What a question!
“But too many of the PCPs hitting the market these days lack an easy to use power adjuster. Why is that? Is it difficult to implement in a design? An expensive-to-provide feature?”

Can you give me a few examples of the guns that lead you to make that statement? I know about the Maximus and Discovery. What are a few of the others?
This is almost worth a blog!
BB

And then he added:

B.B.,
The Marauder is a hybrid that is adjustable, but it requires tools and monkeying around. Cometa, Evanix, Kral and roughly one third of Air Arms’ models offer power adjusters. Who does not? Hatsan, Ataman, Diana, Weihrauch, Benjamin, Beeman, Umarex, Crosman, BSA, Gamo, Career/Sumatra/Air Venturi, Walther, and Hammerli.
Michael

Once he got wound up he couldn’t stop commenting.

B.B.,
Ever go into a “hipsterish” coffee bar wanting a simple cup of black coffee, only to see a menu board with 23 different coffee varieties with 14 different methods of preparation with four kinds of milk and 31 different flavors of syrup? If you’re like me, you stumble out of the place with no coffee but the beginnings of a tension headache instead. When it comes to power adjusting the Marauder is a hipster coffee bar.
Does it have marked power settings and a knob or lever to select them? If my memory of the Marauder is correct, adjusting the power requires using an Allen wrench (maybe two Allen wrenches of different sizes) to adjust two different aspects of the hammer, each of which affects the operation of the other. Then the shooter must use a chrony to determine if the power change is what he wishes or not. If not, Allen wrench in hand, he goes back to adjusting the hammer in two different but interrelated ways. Then back to the chronograph.
I beg you not to be offended, but you have written at great length and in fine, expert detail in past reports on the labyrinthine processes of adjusting the Marauder’s hammer and the effects each quarter turn has on velocity and on the other hammer adjustment’s quarter turns. Marauders are a tinkerer’s dream. But not everyone desires to adjust, chrony, adjust, chrony, adjust, chrony, and so on just to go out and plink for a half hour or go out and eradicate one squirrel.
Some airgunners just want a cup of black coffee. “Strong, medium, or mild, Sir?” That is manageable.
With AirForce, Air Arms (the adjustable models), Cometa, and so on, select one of the marked power levels (no tool required) shoot once to complete the two-step process, and Voila!
Michael

Before I could catch my breath, reader Halfstep chimed in.
BB,
I can give some examples that I own that don’t have any power adjustments at all. The Wildfire and Stormrider aren’t adjustable and I assume that it’s because it would add a lot of cost to such a low cost gun. Neither the Gamo Coyote or Urban are adjustable either. They are both tuned so well from the factory that their power curve almost looks regulated. I think they or maybe the manufacturer, BSA, even refers to it as a self-regulating valve. A user adjustment might throw that out of wack.
You said there would be more description to come so I don’t want to jump the gun, so to speak, but is the Texan SS regulated and if it is, is that adjustable?

And just when I thought the onslaught was finished, reader Vana was heard.

Vana
Hey B.B.
You talking about me??? 🙂
Would love to see a detailed blog on regulated vs. non-regulated rifles.
A comparison of a standard Maximus before and after an after market regulator installed would be extremely interesting. (GunFun1 and Chris USA have done this mode )
Hank

And then more from Michael.

B.B.,
More PCPs with fixed power: Daystate, Kalibr, FAS.
FX has three powers settings.
Michael

I knew I had a blog now! But the comments kept coming. Reader GunFun1 tried his had an answering Michael.

Michael
Think about this also with the power adjustment. Yep it’s easy to dial the power down for the pest bird in the yard and up more for the squirrel out at 60 yards.

But here’s what to think about. What happens to POI/point of impact when the power is changed? It goes up or down. So that means now you have a gun whose shifting impacts at different power settings need to be learned.

I use to do that with my first Talon SS and Marauder. But I found out after time that it’s best to tune the gun for what velocity and fill pressure you want and leave it alone. In other words don’t keep changing the gun settings for a paticular time of shooting.You get a much more consistent gun that way by leaving it set at that particular setting. And what I mean by that is a accurate gun and a accurate person shooting that gun. When your pesting or hunting you need to know where that pellets going to hit in relation to where you aim. Sometimes it’s hard enough learning the holdover or under at one setting let alone multiple power settings.

That was just the introduction to today’s report! Let’s get started.

Two things

I will boil today’s discussion down to just two things — What is an air regulator and what does it do?, and How does the valve behave? In the next installment I will cover power adjusters, but you need to understand valves and regulators first. I’ll start with the regulator.

What is an air regulator and what does it do?

An air regulator is a gateway between high pressure air and working pressure air. In a scuba tank a regulator makes it possible for people to breathe under water by reducing air pressure inside the scuba tank from thousands of pounds per square inch to air at a pressure a person can breathe. In a precharged airgun a regulator reduces air to a pressure that is ideal for the firing valve. The goal is that there is enough air for each shot without wasting any.

Okay, hold that thought in your mind as I talk about a firing valve.

How does the valve behave?

Air valves in airguns allow air to pass from the reservoir to the barrel, where they push the pellet out. Some valves, like the ones in the powerful guns from Korea, are not well-balanced — or at least I have never seen any that were. They start out at the highest velocity and drop in a straight line as the pressure in the reservoir decreases. If the gun has two power levels you can shoot it on low power and get a range of velocities that rises to a peak and then drops back off as described. There is no place where such a gun will shoot shot after shot at nearly the same velocity.

Other airgun valves have a very broad range of shots with the pellet going close to the same velocity. The best one I can think of is the USFT, designed and made by Tim McMurray. It’s a gun that gives 55 shots within 20 f.p.s. and that’s a 10.65-grain H&N Baracuda Match traveling over 900 f.p.s. I had a test target with mine in which 25 shots were in a hole measuring 0.663-inches between centers at 51 yards.

USFT
The USFT gets a large number of shots at similar velocity without a regulator.

Neither airgun I just described has a regulator. And THAT, dear readers, is the most important thing you can learn from this report. You don’t need a regulator to have many shots at consistent velocity.

So — why have regulators?

Here comes the next lesson. Only the USFT valve is balanced well enough to give the kind of performance I just described. It does so on a fill of 1,600 psi inside an enormous reservoir. That valve doesn’t just get built and installed. No, it’s far more than just production and assembly! That valve has to be hand-tuned and adjusted to deliver the kind of performance it does. Think regulators are expensive? So are valves that take hours of fiddling and testing to make them work that well! Either way, you are paying for something.

Now I will bring it all together. A certain company makes a PCP with a well-regulated firing valve. It gets 26 shots that are within 20 f.p.s. of each other. But, if they could supply the SAME air pressure shot-after-shot, the same valve would keep all its shots within 7 f.p.s. And, if they could fill the reservoir to a higher pressure (which is the same thing as building a larger reservoir to hold a greater volume of air compressed to a lower pressure) and still supply air at the same pressure the valve liked, shot-after-shot, their gun would then get 31 shots whose velocity does not vary more than 7 f.p.s.

Result

Would that gun become more accurate? No! Not unless the velocity at which it is now firing also happens to be the most ideal velocity for that particular airgun and pellet combination! If you are willing to spend a few hundred dollars extra, and if the company is willing to offer the service, then have them hand-tune your gun to shoot at the exact velocity at which both the rifle and the best pellet are also the most accurate. Then, you get all the accuracy THAT AIRGUN is capable of! If you aren’t willing to spend the money, or if the company isn’t willing to offer that service (and most of them aren’t), then the only one who can adjust it that well is YOU!

And THAT, Michael, is why the Benjamin Marauder is worth thinking about. It’s also why an AirForce Talon SS is a great airgun within its limits. But don’t expect it to do as well at the lowest power as it does at medium to medium-high power. And finally — BUY A CHRONOGRAPH! It is the only way you will ever know the things I am talking about with certainty.

Why you need a chronograph

In this report I hope you have seen that there is no magic velocity to look for. Each airgun will be different and will need the right pellet at the right velocity to give its best performance. Some guns are very forgiving and are accurate with many pellets at many different velocities. Other airguns are very picky about the pellet and velocity they prefer. When you have a chronograph you gain insight into the hidden data that may be the hinge on which your airgun’s success rides.

What I have not yet addressed

I have said very little about power adjusters in today’s report. Yet this is a report about power adjusters, as well as regulators. That discussion is still to come.

My goal for this report is to give you information that helps you understand what air regulators can and cannot do and what affect a power adjuster will have on an airgun. We got partway there today, but there is more to come.

115 thoughts on “Precharged pneumatics, regulators and power adjusters: Part 1

  1. B.B.,

    Now I’m beginning to wonder what kind of work one has to do to tune a valve? I used to think it was just balancing the power of the valve spring against that of the striker spring. Seems like there is more than that going on. Possibly another future blog post?

    Siraniko


  2. B.B.,

    Absolutely fabulous! I look forward to more on these topics. We have both “camps” here and often debate. Chrony results seem to put the winner in the regulated camp. But, you have shown us there is more. I knew that valves can be tuned, but unless a person has different components on hand to swap out, or the valve is adjustable, what can a person do?

    The only input I can offer is the regulator that I recently installed in the Maximus. 27 shots varied 100 fps on a 2000 fill. Regulated and a 3000 fill, 27 shots had a 12 fps spread. Yes, I filled higher and yes you sad that can be a helpful factor. Either way, the regulator seems to be better.

    As for accuracy, I would expect it to be better. Unfortunately though, it has turned cold in OH. (9 F as I write) I could do 41′ indoors, but other than entertainment, it is pretty pointless.

    Thank you for taking on a most interesting and controversial topic.

    Chris


  3. B.B.,

    As a possible addition to the series, perhaps you can touch on valve tuning. Not too deep, but what does it basically involve. My (totally uneducated) guess is adjustment of spring load. I envision washers, to increase/decrease spring load. Perhaps and adjustable end cap to do the same? Of course, changing the spring.

    Beyond that, I see different components,… valve, valve seat, valve body orifice size, etc.. These I see more used when going from one caliber to another,… not so much as “fine tuning”.

    At any rate,… since we have several here that like to get inside and play a bit,.. perhaps you could school us on some of the basics of valve tuning. Just and idea,… as always. 😉

    Chris


  4. Chris,

    Rather than get wrapped up in you above string of coffee induced ramblings, I thought I would drop down here and start afresh.

    BB,

    Most especially since you probably know more about this than I, should I stray please give me a shove back in the right direction.

    As many know, the AirForce line of air rifles are a tinker’s dream come true. That includes the valve. There are aftermarket stems with larger air orifices. There is at least one stem available where you can replace or remove orifices, giving you three different sizes.

    Another adjustment on this valve is to adjust the valve spring tension. This is easy to do, but requires you to remove the valve from the tank. Please do drain all air pressure from the tank before attempting to do such. The valve spring is used to assist the internal air pressure in closing the valve after the striker has knocked the valve open. By adjusting the spring tension you can increase or decrease the valve dwell time, increasing or decreasing the volume of air that is allowed to escape.

    This adjustment can also have the affect of adjusting the peak of your pressure operating curve. Increasing the tension of the spring will increase the peak pressure and vice versa. When I bought my Talon SS from Mac, I chronographed it and discovered it had an operating pressure of 1800 PSI. When you are filling with a hand pump, that is awesome. Do not think it was wimpy though. H&N Baracudas were going supersonic.

    It also has the affect of shortening or lengthening the curve. With higher spring tension, the power curve is going to peak higher, but be more compressed. With my Talon SS I could get 30-40 shots before I would have a noticeable drop in POI (point of impact).

    While you are in there you should polish the valve stem, valve stem air orifice, valve stem channel, etc. This will help to improve your valve efficiency.

    This is the kind of stuff that is involved in tuning your valve.

    BB, did I get it right?


    • RR,

      Did you know that I may have built that SS for Mac? He wanted an inexpensive one so I arranged to use all blem parts to built him one they sold him at a reduced price.

      Was that the one with the 25-inch barrel? There is a story about that, as well. In fact — you have just suggested tomorrow’s blog.

      Thank you,

      B.B.


    • RR,

      Very nice info. and a lot of what I expected to hear. You did give some nice specific examples. Thank You!

      I was going to say that you have gone and done what I asked B.B. to do, ( a valve tuning 101 mini-blog ), but it would seem that you have inspired him to give it a go anyways,.. and then some. 🙂 Always a good thing. Looking forwards to it all!


  5. AAAAHHHH!!!! BB, what have you done?! You have created a monster! You helped get me into this mess! Now I am getting ready to start rambling on about valve, striker, striker spring, transfer port and barrel length interrelationships. I am most definitely going to need another cup of coffee. 😉



  6. B.B.,

    O.K. Down to Tim McMurray’s USFT. I remember the very first time I read of those was this blog. Was that Whacky Wayne who stopped by with his and whose picture you included? I wondered when you wrote about him on December 1: /blog/2017/12/owning-vintage-airguns/

    Michael


  7. B.B.,

    “And THAT, Michael, is why the Benjamin Marauder is worth thinking about.” Still smiling. And I do have a chronograph. I also still have my first gen. and synthetic stock gen. Marauders.

    My comment about the Marauder was that it is “fiddly” to adjust. What if one desires a PCP he or she can use at multiple power levels with easy adjustment from one to any other?

    That is something the Marauder can’t do.

    Michael



      • B.B.,

        The next generation of Marauders must be on the drawing boards. What an improvement that would provide as a promotional point! The Marauder is accurate, very nicely triggered, ambi-configurable, and quiet. But the competition has caught up, especially in terms of value.

        If a new generation of the synthetic Marauder shaved off another eight ounces, added an integrated weaver-picatinny rail and a power wheel (or even four position power level selector), and 2900 psi fill or not, I’d probably break down and get one.

        Michael


        • Michael,

          With a longer screw and knob and # scale, the port adj. could be tool free. On the hammer, the same. On the striker, the hammer allen could be drilled out/tubed and then the striker allen could go through it. Mod the rear of the stock a bit, maybe add some #’d scales,.. and done.

          I would be very surprised if something is not already out there. I do think, 99% sure, that the 13XX and 22XX series pistols already have them from aftermarket makers. I just got a 2240 that I will be playing with, so I have doing some looking around.



  8. You know from previous posts I am very pro regulator and that is from my experience with them.

    My first PCP was a regulated .177 Walther AR20 FT rifle that was very accurate. On 300 bar fill I would get 60+ shots with under an 8 fps spread. I decided that I was not going to get into formal field target shooting so I traded the AR20 for a TX200 🙂

    But, having been totally seduced by the dark side, over the past 5 years I purchased a pair of Weihrauchs (.177 & .22 caliber) for target shooting and pest control and hunting and recently added a .25 caliber FX. These are all regulated rifles that typically shoot under 10 fps spreads across the fill – you just need to keep the pressure in the green part of the gauge and you are good to go. I will likely get into fine-tuning at some time but for now, its add air, add pellets and shoot.

    My point is that I view regulators the same way as I do automatic transmissions in a car – they add cost and complexity to the vehicle but they are a major (IMHO) convenience. Vehicles are offered with a choice, it is reasonable to suggest that rifles be made available in regulated or un-regulated versions to suit the different user needs.

    Was just looking at the FX Crown which features externally adjustable regulator, valve spring tension, power adjustor (transfer port) and has the option to swap calibers. Awesome machine if you are into no-the-fly tweaking but all the controls would probably be a nightmare to a casual user!!! I like the KISS principle.

    I am pretty heavy into air rifles but I prefer the simpler approach – I will go inside if I need to but other than that I like consistency and that means not messing with things.

    Guessing that for every shooter that is into fine-tuning their rifle to racing car performance there are a couple of dozen who prefer to drive to Wal-Mart, grab a can of pellets and blast a bunch of cans. Think regulators would help the average user enjoy shooting more by simplifying PCPs and allow the serious shooter to concentrate more on their shooting that the needs of the rifle.

    Just my nickel… off the soap box now 🙂

    Hank


    • Hank,

      Well stated. The Crown sounds nice. Are all of those adjustments (tool free)? and have (scales)? for reference? If so,.. drool! Like GF1 said, set it and forget it is nice too. I am not going high end yet, but if I do want/need to play/adjust, I want it to be easy and accurate.

      I do know that I like the Maximus regulated very much. That is my first and only experience with regulators thus far.


      • Chris,

        Yup, tool-less for the settings with reference scales and just an allen key to change the probe and barrel liner to a different caliber or a different rifling twist rate.

        Shouldn’t do this to you but here is a short summary with a couple of pictures…

        http://hardairmagazine.com/news/iwa-2017-day-one-new-fx-crown-air-rifle-announced/

        I thought about the Crown (briefly) but think that if I could do it again I would still go with the .25 FX Royale 500 – I am real pleased the performance of with mine.

        The Maximus is a fun little rifle isn’t it eh! Would be nice if Crosman offered it with the regulator built in.

        Hank


        • Hank,

          Oh My!!! Now THAT is the VERY reason that I do not look at the higher end stuff very often. 🙂

          The interchangeable barrels/liners is most interesting. Diff. twist rates as well. It will be cool to see what they come up with on the ideal twist/pellet combo and publish it., if they have not yet already.

          It is like everything that we all talk/wish about. There is nothing left to want. I am glad to see an air gun company going to that extremes. I am sure there is others too. Though, like they say,… “it’s gonna’ cost ya’ kid”. 😉



            • Hey guys,….. 100% worth the 12 minutes to watch!!!! You will never think about the standard Diabolo pellet in the same way again. Watch it. (good hunting video as well)

              Hank,

              I have tried the Grizzly’s, which to be much the same the same as the bullet shaped pellets. Now, it could well be that I was not pushing them fast enough,.. or with the right twist barrel.
              I do think that this may very well be the next “big thing”,… however,… it may take a fast fps and a barrel and twist and of superb quality to achieve it.

              Thank you for the link.


        • Hank,

          I forgot to add,.. yes, the Maximus is great. I know that I have said it before,.. but for LOP addition,.. the (large) Limbsaver butt pad slips right on, fits perfect and snug and adds a quick 1″. Being a regulator fan, I think that you will like the reg. if you ever do it. I have some good notes.

          Come to think about,… wasn’t that the Grand Daughter’s gun?,…. I understand. 😉


          • Yeah, the Maximus is my Grand Daughter’s rifle but I have to check the sighting for her don’t I 🙂

            Say that you got a 2240 did you? …50 years ago I was less than impressed with any and all of the Co2 pistols I tried, might be time to look at them again. Would be interested in a HPA version with a long barrel.

            Later…

            Hank


            • Hank,

              Yea,.. but I had a $50 Wally card to burn. HiveSeekers’s blogs have been interesting and he has (more than enough) data to back everything up. I am thinking keeping it Co2 based on his results. If you want to push it, you could end up with 300’ish in a 50 dollar pistol! My mod. ideas look to add around 140 with a Maximus barrel. HPA pushes that 140 even more. Just some FYI.

              Later,… Chris


            • Hank
              I had a couple 2240’s with long, long barrels as in Discovery barrels at the time. Would go with a Maximus barrel if I built another one though.

              Ran them both on Co2 at first then converted them over to HPA. Very good results both Co2 and HPA.

              They are very light and easy to point guns for woods walking. Of course I had the 1398 stocks on mine.

              You should build one. And I’m sure with your wood working skills you could come up with a beautiful stock for one.


              • GF1,

                Looking at parts and pieces today for the 2240. Should pick it up on Fri.. You mentioned the Disco or Maximus breech. Is there any advantage to that over the metal Crosman 22XX replacement? You mentioned a screw location, but not much else, other than that they would work.

                I found a place that has “Magnum” in it’s name. Looks to be a 1 stop shop. Even Maximus barrels at around 70, which surprised because the std. Crosman ones are around 20-30. Fore arm’s too. P.A. had 0% Maximus other than common inside parts. You had better know the Crosman # to do a search too.

                Other option would be to mix it up and go Crosman, P.A. and somewhere else to get it all.


                • Chris
                  The Disco and Maximus breech are the same. They have the on hole in a different location in the pellet loading area. But still work on a 2240, 1322/77

                  The steel breech Pyramyd Air links I gave you the other day are the direct bolt on steel breeches that fit the 2240, 1322/77 pistols.

                  And email me that link if you would of the Magnum named website. I would like to see it. And that way you don’t have to post it here if it’s competition to PA.


                  • GF1,

                    Will do. Most likely in the AM. I do not link stuff into E-mails often, if ever, but I am sure that I will figure it out. If nothing else,.. just spell it out. Will do though.

                    And of course,… there is Hi-Flo valves, rear adjusters, springs, ports and a million other things to buy and add. I spent a good portion of the day finding what is out there. A bigger port and Hi-Flo valve might be an option? Or not. Ohhhh GF1,… what have you gotten me into?,…. again! 😉 x10


                • Chris
                  I should point out about the front screw location in the Maximus and Discovery’ steel breech. It’s located back farther under the bolt.

                  The steel breech that’s a direct bolt on from PA has that hole up right before the barrel where you load the pellet.

                  In both cases that screw helps the breech hold down on the transfer port orafice.

                  On wither types of the steel breech I move the barrel band as close to the breech as I can. The barrel band will actually secure the barrel and breech also. I have not any leaking from the transfer port at the barrel from doing it that way.

                  Just wanted to point that out.


                  • GF1,

                    Ok,.. last questions,.. for now. Which is better? Which is going to do the best job? I figure that the screws are meant to line up 1 way,… so I am a bit confused. Keep it simple,.. which one would you get?

                    On the band, I wondered about that and if the stock one was plastic or something. If so, I would want a metal one.


                    • Chris
                      Same barrel band as the Maximus. That’s the cool thing about these pistols and rifles. They are modular guns.

                      And get the steel breech from PA for what caliber barrel you are going to use.
                      They are the direct bolt on breeches for your 224 and the 1322/77’s.


                    • Chris
                      Also while we are here might as well keep the info together.

                      You know you can rotate the barrel band a hair to one side or the other to help the sight and POI errors at different distances.

                      Sometimes POI will shift side to side at different distances. That’s what’s cool about the barrel band also.



            • Hank,

              Be careful if you choose to dive into the 2240 pool. Immediately you will get a steel grooved breech and aftermarket trigger for it. Then an extended probe and longer barrel. Then a custom high volume valve. Then a power adjuster. Then a screw-on metal buttstock.

              I bought one off a guy online that had every mod I listed above except for a power adjuster and wire stock. He even replaced all the screws with Allen heads. I vaguely recall his saying the steel breech was an early DAQ one.

              Why was he selling? He had run out of mods to do and had grown bored with it. I hate to think how much money he had into that thing. He got $100, shipping included, from me for it. That was the first CO2 pistol (well, with an 18 inch barrel) I ever got in .22.

              Michael



                • Chris,

                  I forgot the anodized trigger shoes, gold plated safety bolt covers, and cue ball cocking bolt ends.

                  Many an airgunner has pointed out the irony that the 2240 is popular because it is the most airgun $49 (more now, I suppose) can buy. That’s true, but by the time one is done with it, it is the most money one can spend on a resealed Crosman 180!

                  Michael


                • Chris
                  Just thought I would mention.

                  It’s 14° right now outside and calm as can be with about 2 inches of snow on the ground.

                  Guess what I’m doing. Yep shooting. Got the Mr. Heater propane heater going in the breezeway with a fan circulating the air. It’s a balmy 60° in here right now. And that’s with the window open. I don’t feel any cold air coming in. Got the fan and heater positioned so it blows past the window. 🙂


  9. I’ll throw this out there.
    I have not had any time with a regulated PCP, my highest dollar investment is a Benjamin Marauder in .25. When I bought it all the regulated PCP’s were much more $. I am happy with my choice, it works very well right out of the box. That said, I have made some adjustments to have it fit my tastes better. With some instructions from another discussion form I set it to shoot JSB 25.39’s at about 820 FPS. Now with a 2900 PSI fill it will shoot 2-8 round magazines with only a 10 FPS spread. If I do my part, 8 shots will make a one hole group at 35 yards. As long as I can get the same pellets I will not change where the gun is set.
    Gerald


    • Hi Gerald,

      Excellent shooting to stack pellets at 35 yards! You really know you rifle/pressures to be able to do that. 10 FPS spread is great as well!

      FYI, my regulated rifles will hold under 10 FPS across a fill – for 56+ shots (four magazines of .177 @ 17 fpe); 28+ shots (two magazines of .22 @ 29 fpe); and 66+ shots (six magazines of .25 @ 45 fpe) and still be in the green on the gauge (on the regulator).

      I’m not bragging. Just pointing out that while regulators do add cost to a rifle there is the convenience of low spread, higher shot counts per fill and freedom from having to worry about hitting the right fill pressure to stay on the flat of the bell-curve. You don’t need a regulator to shoot – but they are nice to have 🙂

      Hank


      • Hank
        Thanks for the complement on shooting well. I was posting the FPS numbers there to show that it is possible to have a consistent shot string while unregulated. BTW the FPS starts falling off half way through the third magazine. I do not mind doing two magazines and refilling as my fill device is a hand pump. I have also figured out that this rifle takes just under 3 pumps per shot.
        At some time in the future I will get a regulated PCP. I have a couple on my wish list. One challenge to overcome is when the price is four digits before the decimal it is a really hard sell to the spouse. I may convert my 2240 to HPA. Hiveseeker’s blog has me inspired.
        Gerald


  10. Sounds like we have some interesting reports ahead of us on this subject

    And I should add. Every pcp I see or have keeps screaming regulator to me.

    I still keep thinking about one for my modded WildFire. It’s operating the best now on 1250 psi down to 750 psi. I should be able to fill that gun to 2000 psi with no problem with a regulator in it set around 1000 psi. My main thought though is will the regulator be able to keep up with rapid fire fast action shooting. The Huma regulator I just put in my Maximus will fit in the WildFire. And it does have a chamber that’s about 2-1/2 inches long that fits between the regulator and valve. So that could be just enough area to supply the regulated air to the guns valve. I keep thinking though also. Do I want to pay a $115 more for some more shooting time before needing filled again. Right now I’m thinking yes. Will have to see.

    And my next gun will be a AirForce Talon SS again. In .25 caliber. But this time it’s getting the AirForce Co2 adapter and I’m going to use my Air Venturi 1200 psi regulated 3000 psi HPA bottle.

    I think I’m going to start looking for guns that will accept the Air Venturi bottle in one way or another. The Gauntlet is one that uses that same bottle but with a different name on the bottle.

    And last I will end up with a Wing Shot air shotgun. And I’m definitely going to look into a regulator for it. 3-5 shots is not going to cut it.

    And don’t know if you all are catching this. I’m not necessarily going the regulated route for velocity or reduced fps spread or accuracy. It’s mostly to achieve more shots per fill. Now if the gun does end up with the other things mentioned. Well then great. But yep I would say as much as we say that pcp’s are the dark side. I would have to say that regulator’s and pcp’s are the bright side. 🙂



  11. Wow. This line of bog/comments kind of makes my head spin.
    I read this blog because I enjoy the ‘simplicity’ of shooting an air gun and it can also be quite economical and fun.
    But, I was online looking at PCP’s, with my adult son looking over my shoulder and we discussed some of the costs of shooting a PCP. Looking at the ‘support’ items for a PCP: carbon fiber tank, adapter, compressor(?) in addition to the basic requirement of a rifle, costs tend to mount up (especially if you want a nice rifle)!
    For the kind of money that I would spend on a decent PCP and support gear, I could get an Anschutz .22 (with a known pedigree of extreme accuracy), and good sized supply of Eley Club ammunition.
    Which would I enjoy more? I don’t know, but ‘simplicity’ would favor the firearm.
    I guess that I will continue to read the blog, shoot my Blue Streak (multi-pump pneumatic) and save my dimes and nickels for that Anschutz.


    • Billj,

      Welcome to the blog.

      Cost isn’t the factor when it comes to airguns. It’s really safety and scale. We can shoot in our back yards. I shoot in my house. That’s harder to do with a rimfire.

      We are not trying to make anyone choose between firearms and airguns. Airguns are just a safer and quieter alternative to a firearm, when you can’t get to the range.

      B.B.


    • Bill
      I shoot firearms too. But air guns is kind of a different breed of shooting. I guess I should say in my case is that air guns and making pellets fly accurately fascinates me.

      And another thing. Air guns for the most part are more quieter than firearms. So in many cases you can shoot air guns and not bother anybody. Plus there are air guns that make different energy levels so you can choose one that fits your shooting area.

      And on another point. Pellets are readily available. See what happens at different times what it’s like trying to find certian types of firearm ammo.

      And last if you was to get into air guns. Probably I would go pcp right off the bat. Buy the support equipment you feel will be good for you. And then the thing about pcp’s. You could get a certain gun that could be shot in your back yard as well as your basement. Then as time goes on you can step it up to more powerful bigger caliber pcp’s.

      Just throwing the thought out there at ya. You know what will work for you better than I do. 🙂


    • Billj,

      You sound as if you have a pretty good idea of what you want and do not want. Really, in all reality,.. you are at the best place to be. When I first came here 3-4 years ago,… I had no idea.


    • Billj,

      You don’t need ALL the support items to shoot PCP. I love shooting .22 LR myself but it is a 30 mile trip each way to my brother’s house to shoot ( no interest what so ever in shooting at paper at 25 yards at an indoor range). And that’s only an option on his wife’s off days, since she works 3rd shift and sleeps during prime shooting hours. I live in the suburbs and PCP gives me the ability to shoot whenever I want, day or night.

      There are accurate PCPs to be had,new, for a little over $200 bucks. If you can shoot at your home or nearby I can see the appeal of the Anschutz, though!!


  12. BB,

    Several readers here have suggested that I install a regulator in my Gamo Urban and Diana stormrider. Both of these guns are inexpensive enough that a regulator would increase the cost of each gun by a considerable percentage, which could be viewed as value added if it boosted performance significantly, but would be wasted cash if it didn’t. I believe, and I think that you are about to verify with this particular series, that performance as regards air management and shot to shot stability is dependent on more factors than just the pressure of the air being provided to the gun’s valve, which is all a regulator does, if I understand correctly.

    I wouldn’t want to waste money on a regulator and then find that my striker was gritty or my valve was sticky or poorly sized and matched to my transfer port or any other variables that I may not have even thought of that would still give me shot to shot variations of 20-30 fps in velocity. So I thought that if I tethered my guns to a 74 cubic foot SCBA tank filled to a given pressure that I could get a glimpse of how it would perform on a regulator set at that pressure. I did that at one fill pressure on each gun just to see and the results I got are posted below. I used pellets that were sorted by weight and head size to remove those variables as much as possible. I didn’t worry about accuracy at this point, I just wanted to see how the shot to shot velocity jumped around.

    The Urban seems to have the better valving at this point with a narrower spread from shot to shot, if what I’m doing is even valid. That’s where you come in. If I repeat this at different pressures, do YOU think it will give me any insight into how the guns would perform on a regulator. I was also contemplating doing this to discover how different pellets would group if fired at different velocities and using that to determine when to stop filling the gun’s reservoir.

    Here’s the Gamo graph. I realize that the valve is staying in partial lock at 225 bar and the valve may act differently when it is fed air at a pressure that lets it open normally, but this is the pressure the tank was at when this idea occurred to me. I’m thinking of doing it at 20 or 30 bar intervals.

    Also, Gamo, and I guess BSA as well, call the valve in the Urban and Coyote a self regulating valve. Could you discuss what that is in one of the upcoming installments of this report,if it’s even a real thing and not marketing hype.( I think I’ve even seen it referred to as ” New and Improved” self regulating valve.)





    • Halfstep,

      You understand it well.

      Here is my rationale for installing a regulator. If you have an airgun that’s very accurate and you want to get more shots per fill, then a reg is the way to go. Other than that, it’s not really worth it.

      I have owned airguns with regulators and without. The ones without did very well.

      First establish that your airgun is extremely accurate. Then decide whether it’s worth the investment.

      B.B.


  13. The tethered graph is gradually sloping up because I think I caught my SCBA tank just as it was transitioning to a lower pressure. It’s a little tough to pinpoint exact pressures when all the gauges involved don’t use the same scale or necessarily have the same degree of accuracy at all pressure ranges. But this does show the stormrider’s valve fluctuating over about a 20 fps range as opposed to the Gamo’s 10 fps range.


    • Halfstep
      And that’s exactly what I was referring to the other day when you was going to first try the bottle without a regulator.

      I still think the best results would be from your big bottle tethered to your gun.

      But with a regulator inline so you can set the pressure exactly as you want and not have to rely on keeping the bottle pressure stable for your shot strings.


      • GF1,

        I’d have to buy a regulator to do that and I’m afraid one for a SCBA tank would be even more expensive than one for a gun. I managed to keep a constant pressure on the 90 shot string that I fired with the Urban. That is plenty good enough for my purposes. I just need a little more practice at it. Right now I’m 1 for 2 and will improve, I’m sure. This is new ground for me so I’ll probably make mistakes and need some do-overs as I go forward.


        • Halfstep
          True one the cost for your big bottle or the gun.

          But one thing your test is missing. Shot count. I think you already have your answer for velocity and spread.

          Now how are you going to test what a regulator will produce if you had one in your gun?


          • GF1,

            That’s not really what I’m testing for. To simulate everything a regulator would do in your gun you would need a..well, regulator in your gun. My goal with this little experiment is to see how well the valve moderates the pellet’s shot to shot velocity if it’s fed a constant air pressure, or as near constant as I can get with a simulation. I further want to see if, as that pressure changes, does the valve perform better or more poorly. In my gut I feel like the valve will be more consistent at some ideal pressure than at all others. There may come a point, depending on what I find, when I try to determine at what velocity/air pressure to best shoot different pellets.

            Shot count is going to be limited in large part, I think, by the size of the guns’ reservoirs, anyway, and I won’t have a lot of control over that. Since both guns have reservoirs in the 115 cc range I wouldn’t expect any regulator arrangement to deliver very many additional shots by actual shot count. Maybe as a percentage it would look more significant. Just not much air volume to work with.

            If anyone out there has already undertaken this with either of these two guns you could save me a lot of time (and spoil my fun, truth told) by sharing your findings with me. Matter of fact, I don’t see much here about either of these guns, so I’d be much obliged if any owners out there would share ANYTHING ya got with me.


            • Halfstep
              That’s the point. Your not testing exactly how a regulator in your gun will perform fl you put one in.

              Then get on paper and see what happens.

              Your doing a real world test for sure. But not how your gun will do if equipped with a paticular regulator. Then let’s add this in. Now let’s try a different manufacturers regulator in your gun and let’s see how it performs.

              Will they perform the same, maybe close or maybe totally different. The only way and I mean only way to know is if you put a regulator in the gun. Right?


              • GF1,

                “That’s the point. Your not testing exactly how a regulator in your gun will perform fl you put one in.”

                I’m pretty sure that was the first point I made above.


                • Halfstep
                  Then the point of your test is irrelevant for your gun with a specific regulator in it.

                  What is the purpose of your test then? To see how the unregulated big bottle will work on your gun.

                  That’s the only thing I see from your test.



                    • Halfstep,

                      🙂 Hmmmm?,… how can I say this without offending anyone?,…

                      GF1 and I have gone round and round in the past. This can go on all night. My go to “move” is to say,.. “Your making my head hurt!” and “Out’a here for now”. In fact, I think I just did that move a day or two ago.

                      Don’t get me wrong. I am forever grateful to GF1, but he can be just a wee tad persistent and head strong on occasion. 😉 Me too for that matter.


                    • Halfstep
                      Air flow from one source to another.

                      A 74 cubic foot bottle.

                      A gun with 200 CC’s of volume or whatever it is.

                      Feeding a valve in the gun at a given pressure from that bottle.

                      That’s all fine in trying to find out how the air flows to the valve by that means of air supply.

                      Got that. But you also stated at the beginning of your comment today that people have tryed to talk you into a regulator for your gun. And I got that too.

                      So my question is if I can say it any clearer way than this.

                      What is your next step. A regulator for your gun or not after your test you gave info to today?



  14. Probably should have pointed out for the benefit of anyone that be confused, that the slope was upward because it was in less of a partial valve lock as the pressure declined.


  15. This youtube episode has some visuals and diagrams that make PCP anatomy easier to understand. I think it fits well in this discussion.

    https://www.youtube.com/watch?v=xHU9uWSNN3I&index=3&list=PLJtIBVn6GmaTSkPSH96Vy7HWEdWO9iexY

    This overview of the Mac 1 is worth looking at as well because of how it shows a very different approach with the valve, unusual rotating transfer port, and old school hammer, all out in plain sight. Another very interesting feature is a two groove barrel.

    Speaking of barrels…

    I’ve just read through the series “What is Airgun Accuracy?”. Very informative. Lots of great info in the comments as usual. One really excellent one I’d like to point out about barrel rifling. This is a secondary link from one that was referenced in comments. This site has a ton of great reading material. The history and photos are outstanding. Check out the menu to the left.

    http://firearmshistory.blogspot.com/2010/05/rifling-manufacturing-cut-rifling.html

    This shows why the BSA barrel is advertised.

    http://firearmshistory.blogspot.com/2010/05/rifling-manufacturing-hammer-forged.html

    It left me curious to know which method is being used to rifle some of the common airguns, like L.W., Crosman, but also all the others. I’ve just ordered a Daystate and don’t know how they do theirs. I wonder what machine Mac is using. An older cutting type I presume.

    I imagine this has been stated many times but I find myself wishing this amazing treasure trove by Tom were done in a way that is more accessible, like a forum where users can organize things in great detail. An example, clicking on the *accuracy* heading on the sidebar does not bring up the excellent article above. In the comments there’s talk of a barrel article I’m still looking for.

    Regardless, my thanks to Tom for what is here. It’s outstanding.

    One more observation. This is another comment made in the accuracy article by a user named Walt referring to Tom’s story about Dr Mann and his “Shooting Gibraltar”.

    “This is a very interesting topic. If airgun sports continue to gain in popularity, then it’s possible that a modern-day
    Dr. Mann could emerge to tackle the problem with 21st Century technology.”

    I think the technology that will bring about new revelations is high speed photography. I posted a link earlier from Ted’s Holdover showing pellets beginning to spiral when head size goes from 5.54 to 5.55 mm. The discussion is endless and inconclusive until you see something like this.

    https://www.youtube.com/watch?v=fRN1Am8RBgs


    • Idaho
      That’s why it’s important to test different pellets and weight sort and head sort and skirt sort and waist sort and over all legnth sort and adjust velocity and so on in a air gun if you looking for the ultimate accuracy.

      And just because let’s say your gun you just got likes one pellet and a certain fill and ending pressure don’t mean if I have the exact same gun you have with one serial number difference will perform with the same pellet and fill pressure that works in your gun.

      Test on a individual gun with what that gun is equiped with and on paper targets at the distances you will shoot at is the only way to get a true answer of how a individual gun will perform.



    • Idaho,

      Thank you for all of your work. It is nice and easy with the links posted. I will check out in the AM. Be sure to check out Vana2’s link above. 2 in fact. The one on the bullet shaped pellets is a must watch.



    • Idaho,

      I just checked out the links. The first one is super for explaining the different types of PCP’s and the valve animations are great. That is some good stuff for BB to use if he can. The other site looks to filled with tons of info. and have it saved for future reference. The Mac1 is fascinating with 2 groove rifling. It makes perfect sense.

      All very good links and urge all to check them out. Thanks again. Chris



    • Idaho,

      Most interesting for me was B.C. and the accuracy. Of course he did have some pretty nice “tool’s” to shoot with. I think that there is some real potential there. Bullet shaped pellets have come and gone, but maybe the right twist and fps was never used either. He had good data but also was left with some unanswered questions. Fun stuff to think about at any rate.


      • Chris,

        Given the success with the FX smooth bore, I wonder if that Mac 1 with 2 groove barrel would be the ideal gun for slugs.

        Thanks Chris and Halfstep – glad others also find this interesting.


  16. Another tidbit that may be significant. I did not see this info in the article on the Pelletgage, which of course is all about headsize. Here is the link. (Problem is I’m not sure we can order by die lot – anyone?)

    https://airgunaccuracy.wordpress.com/jsb-labelling-numbers-explained/

    JSB Label Numbers Explained
    The numbers on JSB produced pellets (also sold under Airarms, Cometa and other brands).
    For example on the label on the bottom of the tin:

    JSB Exact label on bottom of tin
    JSB Exact label on bottom of tin

    First number: 8006709
    Second number: 6
    Third number: 4.51

    The first number:
    – 8 = number of the pressing die
    – 00 = personal number of responsible employee in production
    – 67 =personal number of the employee in Quality Control
    – 09 = year of production is 2009

    Second number: 6 = manufacturing batch
    Third number: 4.51 = head diameter in millimeters

    The 2013 production year batches I have seen do not show the “personal employee” numbers anymore. They just show zeros at those positions. The number looks like 8000013 for a pellet from pressing die 8 from the year 2013.

    Die numbers higher than Die 9 make a the total number an 8 digit number. Like 21 00 58 14 : Die 21, production employee 00, Quality control employee 58, Year 2014.

    I for myself ignore the head diameter and just look at the die number when selecting batches for testing.

    Eric
    December 7, 2014 at 19:47
    Why is the die number more important than the head size?

    sven
    December 8, 2014 at 09:05
    Hi Eric,
    To answer your question:
    I, and with me many others, have measured pellet head size ourselves. We found that the head size within a tin of pellets has a variation that is quite large. For example: In a tin with 4,52 on the label the measured head size varies between 4,50 mm and 4,54 mm.
    And that is not just a few pellets in that box but 4,52 mm does not even seem to be the average for the head size in that box.
    This means that the head size printed on the label is not a good indication of the actual head size of the pellets in the box. This makes the head size a meaningless figure.

    The Die number gives the relation of pellet to the pressing die that was used for making that pellet. So next time you buy a tin and it has the same Die number the new pellets will at least come from the same pressing die and will have the same average shape.


    • Idaho
      People that shoot feild target have done figured that out for some time now. That was a big deal with the Crosman Premiere box pellets.

      What I have found is that if you get a good quality pellet like the JSB’s or Air Arms pellets you don’t have to go through all that sorting stuff.

      Why cause they apparently have better better production procedures and quality control than other pellet manufacturers.

      I know deep subject for me. That’s what happens to the mind after working in a machine shop for 32+ years. 🙂


    • Idaho,

      WOW. It is getting a bit long in day for all of that! 😉 My thought is that yes, all pellets from the same die would be best. However, I presume that a die has more than one cavity. There could most likely be differences from cavity to cavity within that 1 die. Then,… all of the pellets roll into 1 big bin. ?,… maybe.


    • Idaho,

      I have bought many different varieties of JSB pellets in the last 9 months or so and haven’t seen those orange labels on any of them. Nor have I seen any numbers elsewhere on the tin that would convey that information. I can further say, based on my own efforts to verify their accuracy, that the head sizes proclaimed on the bottom labels of H&N Field Target Trophy pellets, for example, absolutely, in no way, shape or form, represent what you will find inside the tin. Its leaded “snake oil” and marketing hype as far as I’m concerned. I almost suspect that the Pelletgage people paid them to put that nonsense on the tin to create a market for their own product !


  17. Gunfun,

    It does seem like Sven has tried everything and simplified his pellet choice by die lot.

    For me right now its about learning and understanding what there is to know.

    I’m sure your background helps in a very practical way. I have a pretty fair education in the sciences which is somewhat valuable in understanding the principles, and prior to the higher ed stuff did aircraft maintenance which required a decent education of mechanical technologies of a more practical sort. The fun is in figuring out how things work in a way that can be put to the test.


    • Idaho
      I also have a facination in flight. One of my hobbies since I was a kid has been radio controlled air planes.

      And like BB always seems to bring up when I make a comment is if you search enough it’s probably already been done.


    • Idaho
      And yep should of said this too. If you have read the blog for any amount of time I’m definitely one for looking and figuring things out.

      I use to race motocross as a kid, also built many drag cars. And done things that people said would never work. And proved them wrong.

      So definitely into the fun of figuring out things. And definitely agree that the more info the better. So maybe it sounded like I don’t. Guess it’s just that bi can say been there done that in a sense.

      Ain’t it funny how the deeper you dig into a subject the more complex it can be.


  18. Gunfun

    I have a half dozen or so RC airplanes.
    We must share some genetics or something 🙂

    BTW I found out LW barrels are button rifled. So that is what the Daystate will have.
    And I located the article by BB on barrel rifling.

    Does computer screen light wear on the retina? If so soon my eyes will wear out.


    • Idaho
      Yes the computer screen does. And matter of fact I try not to get on my phone when I’m shooting. Today my eyes were terrible when I was shooting after going back and forth with the comments. Not only from the screen. But just the strain on my eyes reading. My eyes don’t want to focus good after that.

      And yep love the RC flying. I use to fly quicky 500 and 1/2A pylon as well as aerobatic flying. Now I do electric 3D outside flying. Oh also duel and electric helicopters.

      And on the barrel subject. The new barrel process that Crosman is using on the Maximus involves reaming in the process. When it comes to barrels that’s another deep subject of what way can be the best. Definitely interesting though.


  19. Since I’m going the PCP route, I’m considering a pair of the Maximus for grandkids and others on my future field target course.
    These would give me the fun of tinkering.
    Making targets should also be fun.
    All that has to wait for summer.
    By then my brain will be on information overload.

    I’ve not taken RC so far. My latest thing is little guys that can fly in the small open space of my yard. The Champ at only 1.3 oz is fun an easy enough for kids.


    • Idaho
      Here is one of the planes I have had in the past. It fly’s great inside or outside. But it does need to be on the calm side if flying outside.

      And no that’s not me flying but I do fly like that. And this plan is about a 16″ wingspan if I remember right.
      https://youtu.be/DBItbo7Q6tU

      And here is what I fly now. It is around 36″ wingspan. Ways less than a pound and a half and has about 5 times the power to weight ratio. Very responsive to fly. But also very calm if you program the flying surface movement ratio down. I have the first about half of the stick movement slow and gets progressively more as the stick is moved farther from center.
      https://youtu.be/xFQMZTOP0Ug

      And no I can’t fly this good.
      https://youtu.be/MDxHamYEQNU

      But here is a video of me flying a electric some years back. It’s electric and is the same set up like the 36″ wingspan plane.
      https://youtu.be/HRAmsnTMwds

      I know off subject but since we was talking about the RC flying.


      • Oh and on the second video. That plane has a prop system that can reverse the pitch on the prop with the transmitter. Just like a collective pitch on a helicopter. That’s why it can fly backwards.




            • Gun fun

              The 3D flying looks like a lot of fun. Lots of skill in those videos. I have an inexpensive one but decided my flying skills were not up to trying it.
              I’d kinda like to try a big one but there’s all the regulations now so I think not.


              • Idaho
                If you ever do get the urge to try the RC flying. Get a glider with about a 3 foot wingspan and has a electric motor on the front with a prop.

                They are the most forgiving when flying. You can fly them up high with the electric motor. Then cut the motor and they glide around nice and gentle.

                I taught my wife years ago when we started going together in our early 20’s on a electric powered glider. Both my daughters learned on gliders also.

                Fun stuff if you ever give it a go.


  20. I don’t think the power adjuster on the air force guns work well at all. I have seen where turning the wheel from one end to the other did not change velocity that much. I had a cz T200 target rifle that just turning two screws would change the FPS from 500 to 850 and anywhere in between it was amazing how easy it was to get the velocity right where you wanted it. as far as I am concerned every PCP should have that system


Leave a Reply