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roland3
05-04-2007, 11:03 PM
my build is almost complete and ready to test fire. my bolt gap is uneven. it is about .004 to .005 different from one side to the other. about .012 on one side and .017 on the other. is this safe? the trunion is square and looks perfect in the reciever. has anyone ever used 1 oversized roller with a standard to even the gap or should I not worry about it?
drine
05-05-2007, 12:21 AM
I haven't seen it talked about before but for what it's worth, mine is much the same. You should concentrate on the middle and use that as the gap. Turning my rifle over, barrel away of course, I get a wider gap on the left than I do the right. I use a Starrett gauge that is wide enough that I can't isolate the difference in the two. I'd like to hear from one of "seasoned" vets here. drine
texlurch
05-05-2007, 06:22 AM
One of mine is like that also. Using one smaller roller would not be recommended; that wouldn't cock the bolt in the trunnion enough to matter, and would give you uneven locking pressure on the bolt.
97th Signalman
05-05-2007, 09:06 AM
The gap on my CETME is .009" but it is a bit uneven as well. It's been that way since I got it a couple of years ago. I never realy measured for variance but I know that the feeler gage is tighter on one side than it is on the other. I wouldn't be surprised if the monkeys at Century Arms had something to do with it.
:century: :sterb126:
drine
05-05-2007, 07:52 PM
I have a new bolt head, locking piece, and rollers and it still has a bit of difference but not as much. Maybe it's the lock (hump) on the locking piece, maybe something else. The retainer arm holding the bolt head and LP are on one side so maybe that has something to do with it. Just guessing here. Makes you feel good when someone who knows for sure says "yes" that's what it is. Maybe I shold guess some more!
rustypirate
05-06-2007, 06:55 PM
I would have to guess that the difference in bolt gap is due to the pressure on the bolt head by the locking lever which is spring loaded in the bolt carrier and puts pressuere on the top-left side of the bolt head causing it to be slightly cockeyed.

Just measure at the middle of the bolt head, and use the guage size that goes in just beginning to drag.