UFC One Piece Stainless Steel Cylinder w/ Cylinder Head for Ver.3 Airsoft AEG Gearbox

"First and foremost - this will fit a V3 gearbox if you have a bench grinder and some patience.

The CNC'ed section that was formerly a cylinder head is too long, and has extra metal that prevents you from installing this. If you're lucky and have the right tools, it's worth it to grind off the extra metal.

The compression of this cylinder is utterly insane. I went from 360fps on .28's to 450fps on .28's by swapping to this cylinder and SHS' Double O Ring Piston head.

If you need some FPS, this is it. Be warned, it's not plug and play.

"Better, but needs refinement.

The design has been improved since Will S. wrote his. Drops in just fine now and as he stated the compression is phenomenal, especially when paired with a double O-ring piston head.

You are going to want a dremel and polishing compound on the inside diameter of the cylinder. It is nicely electropolished on the outside of the part to a mirror finish, but the inside is still slightly rough from milling the bore. This translates to accelerated wear on the O-ring if not addressed.