[tokiwartooth]

My prob is no matter what single/combination of shims I use, I cannot get a 5 oclock tighten up. Without any shims, my gas screw starts to tighten at 9 oclock.

I can get somewhat of a tighter gas cylinder if I use ALL 4 of the shims.

Is this ok?

 

[buchkshot]

Can you try another gas cylinder? I've used as many as two shims with no problems. Try the three shims and function fire the rifle, if it cycles alright, you're probably good to go. HTH

 

[casebro]

The point of the lock tightening is to hold the front band in place. Sort of 'unitizing' it.

The threads are 20 per inch. Or .050 per full turn. You need 1/3 of a turn to get from 9 to 5, so ummm .017" or so. Use whatever it takes.

I made my own from a piece of sheet stainless, Half turn, .025". Snugged it up, then tapped the band back and forth to find it's best home.

Some day I may unitize it by tig welding it together. I'll first cut out some of the web between the holes in the band, make it peanut shaped. Then the shim, tighten, tap to adjust to my gun/bedding, then remove from stock and weld the inner side, where the web had been cut away. Weld won't show, unitization will be precise to my stock, like the rest of the bedding.

 

[tonyben]

It's okay if you have to use all four so long as your gas ports are aligned. You can also try flipping the gas lock so that the side that's on the back is now on the front and that may change your lockup for the better.

http://m14forum.com/reference/89156-shimming-gas-cylinder-gas-port-alignment-how.html

 

[tokiwartooth]

I took the FH off, and used the commercial gas lock, and was able to time it right with one shim. Cheers everyone!