Just got a Gauntlet and with that a compressor, so I decided to convert my Umarex 850 M2 .22 cal to pcp so I would not have to buy CO2 any more. I got an adapter and a Ninja Paintball 22ci tank and regulator and some spare shims. Screwed in the adapter and screwed in the tank at the factory setting which was like 900 and nada. Shimmed to 1100, still nada. Shimmed to 1200, nada. Re-installed the CO2 and the gun fired fine. Re-installed the adapter et al, nada.
I have done a ton of research on this conversion and while half of it is miles over my head, some of it I could make sense of i.e. hammer spring, valve flow (and I even have a wrench to take the valve apart with--from my bike tool kit no less). Mine is a newer gun, got in in March, and is stamped made in Germany if that makes any difference.
BUT before I go ripping into an air gun for the first time in my life I though it best to ask first. Don't wanna shoot my eye out. Plus, the gun is a good shooter. Bolt is like butter. I don't want to screw it up if I don't have to.
So, any ever do this afore? Any advice?