So, after about a week of thinking about what I was going to do, I decided to make my very first Bolt Piston housed in a copper reducing tee. Because it was my first, there were obviously teething problems, like - the Piston didn't want to pilot properly, and then it didn't want to seal properly and so on and so forth, but I finally got the old git to work, and my god is it powerful when actuated with that 1/2" QEV, the added bonus is the very small amount of pilot volume. It'll make a bolt stick into the concrete wall (accident) at 50psi.
For those who are wondering, the silencer does, actually work.

This was also my first time soldering copper pipe.
I'm going to spray paint it either matt black and leave some copper rings around the chamber and barrel, or spray it dark matt blue, havn't really decided yet.
Specs:
120cm x 15mm barrel
80cm x 22mm chamber
20mm Rubber Washer and Bolt Piston
^ Is Piloted by a 1/2" QEV
^ Is Piloted by 1/4" Blowgun
Filled through a schrader and Check Valve
Just four out of the twelve joints are compression fittings.
http://s194.photobucket.com/albums/z296 ... CF0687.jpg
I would upload more photos, but its such a tedious process to shrink file sizes and all that crap, but will on request.
Let me know what you think...

Edit: This is the new video that me and NiC made of his spudgun that I made him for christmas.
[youtube][/youtube]