Quote Originally Posted by Jon Budd View Post
Which rather explains why o-rings can give mixed results in them...

(is Nick listening ? )
I am listening, but have to go on my own findings, and I haven't come across a comp tube that hasn't been ok,, I am having problems with the smaller diameters remember. I have put o ring pistons quite a few guns now, and they all make the power expected of them, I set up in my HC, send them off, and they make the same power in the other comp tubes .

Why do people think that an o ring seals differently to a normal seal, they both rely on pressure to deform the seal so that it fits the tube.