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akajun
July 10, 2007, 15:35
Ok I built my first fal all by myself two weeks ago. Read the tutorial sticky by Bandit and Headspaced it with the Gauge and pin set from Gunthings. Gauges said .257, had .257 LS on hand, installed it, double checked with gauges, everything ok.

Build number two is the problem. I stripped the bolt, cleaned the bolt, carrier, reciever, and chamber. Worked my way up with go gauge till it would not close on a .268. No go would not close on .266 so I order a .266 cause nearest I got is .263/.264. Anyway .266 LS comes in today and I install, and check with go gauge. WILL NOT CLOSE!!! I clean everything and double check and still will not close.

I pull out locking shoulder and redo gauge checks, says use .266. Just for shits and giggles I put in my .263/.264 in , clean everything again and check and closes on GO but not on NO GO. Whats going on here, did I do something wrong? SHould I put the .266 back in or shoot it with the .263/.264. I checked the .266 with my calipers and with my micrometer both tell me that the LS is .266 and the .266 gauge pin is also.

Mebsuta
July 11, 2007, 01:02
Have usually needed 1 or 2 thousandths smaller locking shoulder than pin guages indicated. Use the .263/.264 if that is what your GO and NO GO guages are telling you to do. A short chamber is annoying and probably dangerous. Did you check with the GO guage before ordering the .266?

Radio
July 11, 2007, 01:26
You have correctly followed all the "rules". While Rifle #1 is headspaced pretty tight, theoretically, Rifle #2 should be just fine. Your locking shoulder is .002" smaller than your pin GO reading, which should supposedly give you 1.632" headspace, spot-on the standard recommendation.

Dude, you've got an oddity, a ghost in the machine when real world parts mate up. Chit happens.

Try the OTHER bolt in the problem rifle, see what happens. Check your CURRENT bolt locking surface, perhaps somebody whittled on it and it's locking funny. Check the bolt face, could there be a burr around the firing pin that is causing havoc? Check your current locking shoulder, did somebody file on it and radically change the locking angle?

Shooting in the dark because what happened to you, isn't supposed to happen. Sorry. Good luck.

--Radio

adam762
July 11, 2007, 01:58
There is some speculation that the pin gauge, being round, allows the edge of the bolt to clear as it begins to cam down, where as the LS has material right up to the edge.

I dunno. I've had it happen too. If you're good to go with the go/nogo gauges now, then that's all that matters, I guess.

ce
July 11, 2007, 08:34
Dude, you need more guages.

You're using the archaic go no-go guages, when there are more precise alternatives.

First you should check with a not-now guage.
Then the maybe-later guage.

Then, if it doesn't close, a no-way guage.
If it still doesn't close, try the way guage.

If it closes on the way, and doesn't close on the no-way, then try the awright guage, and finally the right-on guage.

ggiilliiee
July 11, 2007, 11:11
is the bolt being impeded any where ....top of bolt/ reciever cut out ?....or extractor pocket did ya say the bolt was stripped or loaded while testing.......always a good idea to check with all the parts in the bolt .... ...as a stripped bolt may not detect the shallow extractor pocket untill you have a serious problem shooting it thinkin its ok ..... kinda like checkin compression on a motor ..without the piston rings in it ...just a thought ..be carefull ...

W.E.G.
July 11, 2007, 11:17
Originally posted by akajun
...I put in my .263/.264 in , clean everything again and check and closes on GO but not on NO GO. Whats going on here, did I do something wrong?

Probably maybe.

Sounds like it fits just fine now. Shoot it for a while and see if anything changes.

Don't go nuts taking that locking shoulder in and out. Otherwise you'll soon need an OVERSIZE locking shoulder.

I have one that gave me a similar experience, and ended up real tight. I'm gonna just leave it that way.
http://www.falfiles.com/forums/showthread.php?postid=466926

ce, your method is too complicated.
For all my builds I now just use the fugk-me!!! and the fugkin' A!!! gages.

akajun
July 11, 2007, 12:43
Im going with it, hopefully Ill get to shoot it next week when Im off.

CE, your a retard, :biggrin:

Radio
July 11, 2007, 13:21
No, ce is pure wholesome entertainment, white as Milk and peeing all over everything.

ggiiggiillee is the "retard" :rofl: as you put it. No, that's funny, but undeservedly harsh. Even so, he'd have you check headspace with the extractor installed. Must be that European gunsmith training...

Yeah, that's it... I've been long convinced that Randy is actually SPLAT. :rofl:

Going back to playing Led Zep cuts again,
--Radio

Mebsuta
July 11, 2007, 15:47
Gillie rulz. ce teh master. I have different brand of guages than him though. Mine say:

1. Not tonight
2. Well I might
3. Oh all right

Yeah

Just like a laydee, she'll keep you guessin through the night.

tim503
July 16, 2007, 23:17
Originally posted by Mebsuta
Gillie rulz. ce teh master. I have different brand of guages than him though. Mine say:

1. Not tonight
2. Well I might
3. Oh all right

Yeah

Just like a laydee, she'll keep you guessin through the night.

Gotta love those Sabbath gauges. :cool:

Mebsuta
July 18, 2007, 01:15
U got it!