Air force .257 barrel

[Jeremy1982]

Does anyone know of anybody else selling the .257 drop in barrels aside from R&L?Reason I ask is cause all the have are 18 inch right now and the email I got back was it will be awhile before anymore are sold due to the blueing process being done outside/Winter.

[Gippeto]

Doug (dyotat100) does a lot of work with the AF rifles and has a solid reputation...would shoot him a pm if he doesn't reply here.

Al

[deadguy]

I have the 18" RL .257" barrel on my CondorSS, and it works great.  It will shoot either JSB pellets or 51 grain slugs accurately.

[Jeremy1982]

Thank you,that was what I also wanted to know.You said 51 gr???Which one?I have the NOE 51 gr .253/.255 mold.I figured if I run a little more tin in the mix I can get them to drop .257.If not I can begal the mold with HVAC tape and def. get .257

[deadguy]

I have the .253/.255 version of that mold.  The bullets drop around .256", but after a coat of VHT epoxy paint, they are a good .257-.258" and fit the barrel chamber snugly. I shoot it from my CondorSS.  You need to keep the muzzle velocity above 825 fps to have acceptable accuracy at 50 yards or further.  With the stock valve and top hat plus the TT heavy hammer with slap mod and heavy spring with power wheel between 11 and 12 gets it to 850 fps.

[Jeremy1982]

I can get them up fast with no problem.I can sail the 51 gr at 930 fps on power setting 5!I found a .257 barrel from a member here so hopefully ill be putting some lead on target before to long.I just hated to buy those molds and get no use!Actually,lol..I have.I got my son who is 7 to shoot with me a few days ago.He uses his 760 pump and I have a hatsan edge I've only shot a few times due to sucky accuracy and horrible trigger.I shot some of the 41 gr threw it and at 20 yards I was knocking the tops off soda bottles.Moving maybe 350 fps but it was dead on!!

[deadguy]

Are you using the AF escape to get 930 fps?  If so, I may have to look at getting an Escape valve!

[Jeremy1982]

Yep.stock Escape valve.The Escapes are pretty stout,only down fall is the smaller tank.I understand the concept of quick/easy fills but its a air hog.On setting 5 I'm using roughly 200 psi per shot.Right now I'm set up for jsb 34 gr on power setting 3 for a avg of 980 fps for about 8 shots (using about 150 psi per shot).Also I have a 24 inch barrel which also plays a part

[deadguy]

I went and tried using the tank/valve assembly from my wife's TalonP on my CondorSS, and it did increase the fps, but only by about 20.  It looks like one of the "extreme " valves out there will be needed to get this bullet above 900 fps in an 18" barrel.

[Jeremy1982]

the barrel is a big part.I was told by AF that the talon p is just the Pistol version of the escape!All is the same except the barrel.On avg from what I've experienced with air rifles including the big bores is,every inch you add it gets you 10-12 fps faster.until you get up to 32 +.then it slows cause the drag.Im thinking of putting a C fiber tank on mine.I already ordered a 380 ci 3000 psi tank for more shots but I think with the 4500 psi I could get up over the 1000s with a 50-60 gr slug.that would stretch her legs.

[Tony Fryery]

What valve are you running? Valve and hammer play a big part in a .257 build. I have 2 airforce condors set up running .257, ones a 27-5/8" barrel with r&l valve in a 3600 psi tank, that I shoot at 3400 psi fill pressure. The other is 32" barrel running Doug's valve and a 61ci 3000 psi tank. That rifle will sling 60 Gr at 1100 fps with the power wheel on zero and it'll push 81 gr at 990 fps average over 5 shots.

[Jeremy1982]

right now I'm just running the escape stock valve.Until I get my new tank it does me no good to up grade the valve with such a little air supply (213 cc I believe).I have a 380 cc on the way though and a 6 mm valve stem.Gonna prob. open the spring retainer up a bit and install a conical spring.See what she does.I got a 27 inch 257 barrel already and with everything stock I can sling a 51 gr at 945 fps on power setting 8.Id really be happy if I hit low 900s with a 70 gr which I think is well in reach after I play with the valve.Really just playing around before I ask Doug to whip me up a valve.

[Tony Fryery]

You're going to need more volume and pressure for a bell curve. My 480cc, 250 bar tank does OK with a bell curve filling to 3400 psi and using a 115 gram hammer and heavy spring to open it. Running Doug's back end setup 61ci tank, hammer, valve and spring, I'm using 3200 psi to get 5 consent shots with a small curve on the 81 grain bullets. The smaller tank setup does 9 shots at 3400 psi with the 60 grain at 1020 fps average. Starts around 1010-1030-1010 on 9 shots. That's using r&l valve, 115 gram hammer and heavy spring. Cedric, Doug and Mike-aka Knifemaker can lead you in the correct direction for this build.