[Crunchmeister]

Yeah, parts don't all fit like they're supposed to. I've been discovering that myself as I'm starting to delv into the upgrade thing myself.

I upgraded my CA M15 rifle yesterday. I installed a Systema red polycarbonate piston, Systema spring guide, and a Systema silent piston head / cylinder head set. Also threw in a Prometheus MS110SP spring. BTW, my stock CA tappet plate is yellow as well. Looks like I'll be having to replace that as well soon. It's showing some wear on its edge where the cam from the sector gear connects with it. Ugh... more money to spend on this gun. lol

Now, initially, there was a fit problem. The stock CA cylinder seems oversized. I couldn't get ANY compression with the Systems piston assembly. When I blocked the nozzle with my finger and compressed the cylinder, all the air would leak out from around the piston head o-ring and out the back of the cylinder. I had to swap the Systema o-ring with the stock CA one in order to get a positive seal. It does work great with the CA o-ring though. I get what appears to be excellent compression now.

Now I test fired the gun, and it does appear to hit quite a bit harder than it did while stock. I'll be receiving my chrony on Monday or Tuesday, so will be able to give some numbers then. But I was able to get results similar to those with my JG MP5. I can easily punch through the bottom centre and almost through the inner edge of a coke can. I'll post some numbers in Kokanee's Prometheus spring thread when I get my chrony.

Good luck getting the gun working.