Is shimming the m14 really necessary?

^^^this... Also, at one of 45ACPKING's clinics (last year, I think?) he mentioned peening the barrel shoulder (where the gas cylinder sits against) as an alternative to using shims. Displacing just enough metal to ensure a snug gas lock at 6 o'clock.

I think he may have been suggesting peening the shoulder to build up material slightly to correct an over indexed barrel. That's the other end of the barrel. I have not heard that the thin shoulder where the gas cylinder shim sits is wide enough nor would you have much control over the tension. Buy the shims.
 
I've got one of the dominion arms socoms from last year, and in attempting to accurize it, I'm finding the gas ports don't line up, can't go all the way into the barrel.
Anyone found this to be a problem with these? As near as I can tell, there isn't a port hole in the barrel at this location, wondering if anyone has any experience accurizing these? Gas lock does seem a little loose, and flipping the gas lock doesn't do much (plus puts the flash hider out of alignment, since the gas lock isn't symmetrical).
 
I think he may have been suggesting peening the shoulder to build up material slightly to correct an over indexed barrel. That's the other end of the barrel. I have not heard that the thin shoulder where the gas cylinder shim sits is wide enough nor would you have much control over the tension. Buy the shims.

it may surprise some, but when I learned to tune and build these rifles I was not taught to use shims. I was taught to roll swage the cylinder boss shoulder forward. I have been practicing that method on other peoples rifles since 2005 and my own before that, after being shown that after just a few hundred rounds, those shims are pounded pretty good.
not all shims are created equal and the only ones I'd even recommend are ones I've gotten from brownells.
there are a lot of little tricks and methods practiced by smiths that aren't posted in the forums, roll swaging the gas cylinder boss shoulder is certainly one of them.
I'm kinda in my been there done that phase as far as building m14 rifles go...... checked # 423 off the books just recently and that will be the last one if I can help it LOL
 
The only man who can put M14, Ebola. the NDP and flu shots in the same message! I was hoping for a flatulence joke with all the talk about gas lock.
Except for the M14...the word "crap" fits the other 3 very well. Thanks Barney.
 
Back
Top Bottom