Forgeron,

I weighed some parts a little while back.
-Piston Assy incl. seal is approx 209g
-Piston weight is approx 28g
-Piston stroke is approx 82 mm.
My TX is Mk2, I understand Mk 1 and Mk 2 are "short" stroke. Also worth mentioning, its 0.177. These are fitted with the heavy piston weight as std (also adds 13.2 mm of spring compression). I understand the 0.22 version has a smaller piston weight and presumably this adds less spring compression. In any event I've seen several recommendations of removing the weight to smooth the firing cycle. I did this and it did improve things. Hope all this data you are collecting is being compiled into a useful database

Risen,
No problem. This is my first TX so afraid I can't pass comment on tolerances getting worse. This one was manufactured in Feb '99 according to AA so obviously been a bit baggy for a while. I'd like to make some new plastic rings to tighten things up a bit - 3 point contact instead of full circle would allow it to be tighter but the ring runs over the cocking slot so that's not an option.

BMP01