I bottled my .25 ATP2, put a different set of baffles in the QE with a telescoping shroud, added a nylon insert in the hammer face to even further reduce sound.Very fun gun. Stock I could only get 9 consistant 643 fps shots starting at 2600 PSI. Bottled it makes 31 FPE for 75 shots avg 747 fps with JSB 25.39 landing 0.5" groups at 25 yds. Between the short barrel and small volume it is hard to make velocity. Barrel lapping picked up a few FPSFirst mod should be to drill the hammer set screw and add nylon chord to lock the hammer setting. The hammer set screw is known to creep.
Oh it happened...Posted a build thread on the way:https://www.gatewaytoairguns.org/GTA/index.php?topic=147540.msg1502071#msg1502071
It's all DIY, some aluminum billet $15, Carbon tube $18, 350ml Carbon Cylinder $90, Hi Pressure paintball type reg $15, gauge $10, washer baffle $6.Some hardware and MDS Nylon.