Jim Crawford (Login BlueMeanies) Crosman Forum Member from IP address 22.214.171.124
but looks can be deceiving.
Lets see. over the last month or so I've tweaked the AS2250 quite a bit.
1st: Upped the pressure behind the pellet to 1800psi.
2nd: Beefed up the hammer spring.
3rd: Made a 1018 steel hollow probe bolt and cocking lever.
4th: Put anti-friction rings on the striker.
5th: Beefed up all seals.
6th: Made a metal transfer tube.
7th: Made a Delrin poppet.
8Th: Made a 12" shroud.
9Th: Had Leupold change the scope parallax from 60yrds to 25yrds.
10th:Changed the scope rings to a medium from a low.
11th:Waiting for a Pacific Pelletguns two stage trigger to arrive.
End result, went from 685fps w/25.4gr pellet to 790fps with the same 25.4gr pellet. 35.2fpe! Not a leak to be found anywhere.
Very pleased with how everything turned out. Raising the optic really helped with allowing for a much improved cheek weld. Groupings are good now but should be great after the new trigger goes in.
Going to have to change it's name to the turkey tenderizer -at least until rabbit season opens.
This message has been edited by BlueMeanies from IP address 126.96.36.199 on Mar 28, 2011 1:15 PM
(Login twhooper) Crosman Forum Member 188.8.131.52
I like it..!
March 28 2011, 4:57 PM
Im a fan of modding the XT. Mine's still CO2 but shrouded and hotter valve among other things. Have a Hawke AO scope on it. Curious about the metal transfer tube. Is that like the poly tube transfer port? What ID did you use please?
Be Well... Tom
"A fear of weapons is a sign of retarded sexual and emotional maturity." - Sigmund Freud
Jim Crawford (Login BlueMeanies) Crosman Forum Member 184.108.40.206
Flat on the valve end and
March 28 2011, 6:27 PM
a 3/16 OD "nipple" at the barrel end. This extension is approximately .05" long. The barrel port has been drilled out to 3/16" and the nipple fits into that hole. As a result, the transfer tube effectively extends flush with the ID of the barrel bore.
the port in the B&A valve. I have the same valve and needed to drill it larger with a #18 drill bit.
Also, I changed the inner valve spring to an external style. There are posts on the yellow somewhere that show this.
Tons of brass can be removed from the inlet side of the valve as well. Increases volume.
The ridged transfer tube gave me a 20fps bump.
Getting the hammer spring strong enough to open the valve quickly took some fussing. I used a spring that I bought at a machinist supply store here in San Diego. It has a larger diameter than stock so both the striker and end cap had to be bored out.
Make a Delrin spring guide that slips inside of that spring. Keeps the energy going in only one direction.
The most profound boost in energy came from making a Delrin poppet and getting rid of the stock Crosman with it's mystery goo seal. At such high pressure, seems the poppet gets smooshed into the valve body. This translates into the poppet effectively taking longer to reach full open. The Delrin poppet opens crisply. It's important to get that poppet open as fast as possible.
were necessary on this AG because of the super strong hammer(striker) spring. The bolt would bind because of how hard I had to pull the cocking lever to cock the gun. It was wedging in the tube. Delrin rings made it slicker than deer guts on a doorknob.
CO222 (Login CO222) Crosman Forum Member 220.127.116.11
Sounds much too low.
March 28 2011, 7:19 PM
If it seems to hit a wall of 20fpe then I'd check carefully for leaks. Use the tissue paper
over the breech technique. A leak can have a regulating effect, any more air only serves to
make the leak worse. Had it on a pumper with plastic breech flex.
(Login Yellowdman) Crosman Forum Member 18.104.22.168
Awesome TT Jim!
March 28 2011, 7:35 PM
I was curious what pressure you were running when I read an earlier post you did. I was getting 31 fpe with the 25.4gr pellets and the senior bigboy 28.6gr pellets and I had a leak at my TP seal. I took everything apart and made a new seal and now I'm getting 33.3 fpe on 1600psi and I'm very tempted to switch to 1800psi but I might wait a little since I'm building a shroud for mine which I'll post some pics next week. I'm stoked you passed my numbers but I'm a little jealous too! SWEET!