bolt length

[NZ kiwi collector 0]

Hello guys, this is my first post at this forum but have been reading the posts for awhile, I'm from New Zealand and I'm just amazed what you guys are allowed to do with your toys and how cheap and available everything is.

I understand that some of you move the gas block back to gain more pressure when you shorten the barrel, I think Tromix talks about up to 4" with a short 8 - 10" barrel, what I'm not clear on is what holds the bolt still to the rails, I would have thought if you took that much off the bolt part that is pushed by the piston then it would no longer be contained within the gas tube at full rearward travel and would jam against the gas tube housing face when it returns or will the spring guide rod keep everything where its supposed to be, thanks for any help, its one of those can't sleep at night till I figure it out things and it bugs me.

[TonyRumore 1,332]

You are correct, the bolt carrier comes completely out of the gas tube on the short guns......but it manages to find it's way back in without a problem on most guns. Occasionally, I have to weld up the carrier a bit to tighten it's fit in the receiver, but that is not a common problem.

 

Tony

[NZ kiwi collector 0]

You are correct, the bolt carrier comes completely out of the gas tube on the short guns......but it manages to find it's way back in without a problem on most guns. Occasionally, I have to weld up the carrier a bit to tighten it's fit in the receiver, but that is not a common problem.

 

Tony

Thanks Tony for the answer, I'm amazed that it pop's back in the hole with out being contained when the bolt is to the rear, is guess the force of rearward impact would move it up but the spring pressure closing it would force it back down on the rails.

Also when you move the gas system back I expect you are decreasing the lock time of the bolt and increase the chamber pressure, is the action of shooting seem alot snapper THANKS

[6500rpm 670]

Just thought I'd share this little trick that I learned from Azhonkey for a 7" AK pistol build. You can use a peice of tubing, or in my case part of the cut off gas tube, and weld it from the bottom to the rear sight base and grind smooth to act as a guide. With the cover in place, you never see it, and all it does is keeps the upward travel of the piston to a minimum and guides it back into the base/tube.