The Hall of Power

Power Rules! OK, in this thread at least… 😀

Let’s see, the 3 guns I have right now that are power guns would be 2 Barnes guns and 1 Condor.

I’d tell you all about the Condor but the builder/tuner already has, it the gun Cygnus made that got the DAQ barrel upgrade. The power he posted for the gun is repeatable and I saw the same numbers if you were wondering. I can’t say I like the valve much as I had an initial spot of trouble with it (that Cyg helped me through) and the fact that there are better designs out there. It does shoot good though and is accurate. I cast pure lead slugs for it and those shoot better than the Hunter’s Supply slugs. At 50 yards it will shoot sub 1 inch groups without the shooter having to master a special hold or technique. Good Lord is this gun loud though!! I might as well shoot the .357 magnum in the yard!

The next power gun is the Barnes Prairie 3 bench rifle. This is a heavy gun not meant for hunting, just target shooting. It has a barrel about 30″ long inside a full length shroud. It is a .32 and the power output is adjustable via hammer throw and spring pre-load. There are a dozen combinations of presets (more if you consider how easily the spring can be swapped) but between overlaps and minor differences, it boils down to 3 significant power levels. But since the gun can shoot slugs from 80 to 220gr (tested) the combinations go way up again… The lowest accurate power is about 80 FPE and the highest is right at 250 FPE. On high power the gun is not “whisper” quiet but enjoyable to shoot without ear protection while still doubling .22lr power (normal rounds). On low power the gun is indoors quiet. The gun has posted sub-moa groups at 100 yards and I’ve also posted groups at 43 yards on low power that had from 15 to 30 shots in the same hole. Yes, it is an extremely expensive example of the airgun hobby but it performs great and is a wonderful example of craftsmanship.

The last power gun I have right now is the Woodsman, also by Barnes. This is my favorite airgun ever (with my long lost 760XL a distant second). This gun is a power gun by most standards but not nearly as powerful as the peak of airgunning. It is a dual caliber gun with a smoothbore .62 barrel and a .32 insert. I love this gun for the fact that it does so many things so well. Most convertibles really only excel at one thing and at best are passable at the other uses. This gun does three things very well. It shoots .62 550gr slugs at 450 FPE into better than hunting groups at 50-75 yards. At 43 yards, that smoothie has recorded many clover leaf groups. At 75 yards, hitting groundhog size targets is routine. Pretty damn good for a slug gun and far better than deer hunting in these parts requires. Second, it is a bona-fide air shotgun that can actually take game (and has) at 35 yards. I usually make shot shells for the gun that get muzzle loaded as the load I like is too long for breech loading. I use .25 ball and number 6 or 7 shot and combinations from a total weight of 500 to 700gr with the best performance at about 600gr. I don’t use a barrel choke but make the cartridges with varying opening resistance to control the pattern. It actually works well and I’ve posted slow mo videos of targets that show the results. The last thing the gun does well is shoot accurately. With the .32 rifled insert the gun shoots to a max of 280 FPE with a 250 FPE slug able to shoot MOA groups consistently. In fact, this insert barrel has posted a bunch of 3 shot clover leafs at 100 yards. Yes, it has also posted 5 shot sub-moa groups but I usually get all happy and picture greedy if the first three shots are touching! Really, I’ve shot so many sub-half moa groups with this gun that if the first 3 shots are not touching (at 100 yards) I’m disappointed and consider the group a so-so effort on my part. One of my favorite groups with this gun was a 5 shot group at 150 yards that I posted several places (including here I believe). It was about 2″ or so but thereal story was that I shot it in a 10-20 knot breeze. I was pretty damn satisfied!

Anyhow, I’m looking forward to my next “power gun” that promises 700 FPE or so in .58. I’ll post groups ASAP!

guess im first with AF conversions

my first project was .308 with and A & B barrel 24″ long from midway, valve was an over sized thing much like the original Af valve, but with no return spring, and relied on the oversized delrin to close the valve…it worked, with power of around 180 fpe with 119 grain softlead…it was upgraded with quackenbush barrel and i got the following

Grain ➡ FPS ➡ FPE
119 ➡ 872.49 ➡ 201.2 308 for sale, powerwheel at 6, 230 bar
119 ➡ 864.7 ➡ 197.6
119 ➡ 846.44 ➡ 189.4
119 ➡ 842.2 ➡ 187.5
119 ➡ 820.06 ➡ 177.7
119 ➡ 807.69 ➡ 172.4
119 ➡ 797.53 ➡ 168.1
119 ➡ 781.06 ➡ 161.2
119 ➡ 774.37 ➡ 158.5
119 ➡ 750.88 ➡ 149.0
45 ➡ 1156.37 ➡ 133.6 refill to 230
76 ➡ 969.48 ➡ 158.7
83 ➡ 944.52 ➡ 164.5

using a simelar design a guy named mr. smith wanted a crazy powerfull .22 he wanted it to be as crazy powerfull as possible, even though i warned him accuracy would go to hell……so i made it do 101-105 fpe with EJ’s…..with mostly stock AF parts and a suped up .308 valve, and hammer spring….of course as physics would have it pellets went sonic and accuracy went all to hell….

this is what happens when you shoot a 119 grain .308 at around 160-180 fpe into a log….YN split the log with an axe, and i think i speak for us both that we where quite surpriced

i then spent about 2 years developing the valve you see in this clip

its a totally different beast…..and the word is beast it is fucking powerfull….and it scales nicely with just about any caliper

in .308 it could make about 250 fpe with 119 grain, but i moved on to .457 since i had a 30″ DAQ barrel

it could do 15 shots with .457 roundball between from 1100 fps dropping to 1000 fps with a slight bell curve starting around 1050 going up to 1100 around shot 5 and then down from there, from a fill of 250 bar

on the hog hunt i got some 500 grain slugs from butcher45 and decided to see what i could make it do….601 fpe

problems with the 45 barrel in the AF frame is
1 barrel is so thick that its hard to get enough hammer weight in there
2 hammer spring is so powerfull trigger components have to be modded
3 the rifle is very light out front or but heavy you might say…because of the imense recoil this makes it hard to shoot….i couldnt shoot it personally…couple of guys on the hoghunt shot it just fine and got it to group….but it could use a very heavy muzzleweight

as with anything powerfull both .308 and 45 was very loud…..exceeding my .17hmr by far…not neighborhood friendly…not to mention the dangers of bigbores….it had no problems hammering a 405 grain hardled slug through a pc cabinet and through the psu and out the other side….so i dropped back to .25 😉 however if you want the schematics for the bigbore valve i will share if you promise to make one for me as well

needed two thumbs to cock hence the wings on the breech

it was long ….so you could use it as a fishing rod when you run out of air 😉

to put it all in perspective my 45acp makes around 550 fpe, 44magnum is around 750 fpe(with regular factory loads), 9mm is around 350 fpe….

conclusion….i think i hold the record for most powerful AF based airgun with 601 fpe witnessed by Butcher, and the other guys on the hog hunt

Alrighty then…let’s get the list going.

Not an AF design, this is an airgun that I designed using a valve type I found on a spudgun forum. Referred to there as a piston valve, it is in actuality a type of partially balanced spool valve. The advantages of the spool valve, when actuated pneumatically, are VERY fast opening time, and VERY high flow rates.

I also found a program called ggdt (Gas Gun Design Tool) on that website. It is used to model the airgun, trouble shoot design problems, trade and/or adjust variables, etc. …without having to build it first.

http://www.thehalls-in-bfe.com/GGDT/

I’ve used ggdt to model two other airguns which have been built. In both cases, the predicted MV was within 20fps of what the completed airgun performed across my chrony. (F1) This with both co2 and air. It’s a very impressive and useful program.

Basic specs;

Muzzle loading airgun, one shot per fill.

Barrel: .120″ wall 1026DOM, bore dia: .760″ , 36″ length

Pressure: Designed for a minimum yield pressure of 9000psi, hydro tested at 6000psi for 3 hours, for a max operating pressure of 3000psi.

Chamber volume: 10 cu.in. (One shot per fill…) 😎

I’ve not been able to work on this in 8 months, and until I get a decent group, there will be no chrony data. 🙁

The ammo I’m using mostly is .758″ 550grain foster type slugs of my own design. I’m casting them from a split mold which I made. I have a push mold, which throws 830grain fosters, and plan to build another split mold for 1000grain slugs. I also have a mold which I’ve used to cast and swage 520grain diablos.

ggdt predicted performance @ 3000psi N2:

550 grain foster: 918fps for 1029.3fpe
830 grain foster: 804fps for 1190.8fpe
1000 grain foster: 755fps for 1264.5fpe

I’ll update this with actual chrony data when I have it, I expect the chrony readings to be reasonably close to prediction…we’ll see.

Interesting design details:

The second airgun I designed and built. I’ve learned a lot since then. (MkII is at the “napkin” stage….I expect 10-15% more power from it.)

This sucker weighs almost exactly 15 pounds.

The spool valve is pneumatically actuated with a conventional hammer valve. (Although a fairly large one.)

ggdt puts the valve at full flow in just less than 1 ms.

Some old pics of the original internals and construction can be seen here, along with a note or two on how things were altered as faults showed up;

http://s245.photobucket.com/albums/gg76/gippeto_album/High%20pressure%20co-ax/

And a reasonably short, and not too boring video.

http://www.youtube.com/watch?v=rg8z-xglmYI

If anyone has questions which I’ve not answered, feel free to ask.

Otherwise, Let’s see what ya got!

P.S.:

In the interest of not creating “Ill Will”, I will content myself with last place until the chrony and supporting video demonstrate otherwise.