Quote Originally Posted by Andrewjames View Post

one question, i will have a tinker with the spring and length of bolt, but was curious as the the length of bolt you ended up using..

will post pictures soon and maybe some results

though i am also working on a brass chambering section - idea is to lap the muzzle and breech end of the barrel for smoother pellet transition and exit which i wanted to finish before doing any chrony work..


cheers
Andy
I can't recall offhand, if I have some time next week I will take it apart and measure it all up for you. I can tell you that when cocked the allen bolt protrudes from the rear 9mm (not including the head, but including the o-ring sitting under the head). When pulling the bolt back the hammer doesn't connect with the spring until over halfway through the stroke. You want the end of the spring guide sitting just inside the hammer.
Bear in mind that my pistol is a .177 with a longer than standard barrel so you will have to fine tune it to .22 in (presumably?) standard barrel length.
.22 should be more efficient, but I don't know if that will be cancelled out by the shorter barrel.

Lapping/re-crowning the barrel is a very good idea, Crosman leave them a bit rough. To crown I put them in the chuck of a drill ('the poor mans lathe') and use carbide bits, files and wet 'n dry to dress the muzzle.