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Posted: 2/29/2008 8:37:29 PM EDT
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I have a question for the experts out there? I have built one Romy G, matching serial number gun and had no issues. I now have two additional Romy's to build one is a matching number gun and one is mis matched. Now I understand the need to check headspacing etc when using mis matched parts, however my question concerns how do you "Fix " a gun which may have a headspace issue when the barrel is already pinned in place. I would assume it would require removing the barrel etc and attempting to correct the headspace issue but how exactely is that done? Can headspacing be checked prior to fully assembling the rifle? Also how many people have really run into the problem of headspacing with an mismatched AK? I'm just trying to avoid as many problems as I can with this build any advise will be greatly appreciated. |
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Rifle is headspaced by grinding the back of the lugs at certain angle. Distance from bolt face to the back of each lug is not same. New bolts have enough stock on the lugs for purpose of correct headspacing. I'm guessing that special fixtures, tools and measuring instruments are used, not trial and error, or moving barrel back and forth.  Above: brand new bolt headspaced by Arsenal.  Same bolt: showing cam surface. New bolts do not have these surfaces ground. This surface is ground at a compound angle and is correctly timed; it initiates bolt rotation at proper time, otherwise the bolt will not close. I do not know any AK gunsmiths that do this kind of headspacing. |
Can be head spaced with out rec ,need trunnion barrel , bolt. $ 45.00 plus postage..Pat |
Can you explain the procedure on doing this for those of us eager to learn ? not to take any business away from you, just curious more than anything. |
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Clean chamber , insert head space gage in bolt, put in chamber if it closes on a no go or field gauge it needs to be adjusted. Pop pin, push barrel ether way as needed until it will accept the go gage and not the no go. ( bolt lug will bottom out on the trunnion with the go and will not bottom with the no go. Once satisfied that HS is ok drill/ ream oversize pin hole.Make a pin to fit any where from .0005 to .001 interference fit will do.Go just large enough to clean up the pin hole to good metal do not go larger than needed. You need the barreled trunnion and bolt to check HS with or with out rec... If it will accept the no go and not the field you are good to go . use only the bolt and guage and about 10-20 lbs of finger pressure do not force it. Pat |
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You can also compare the head spacing against a known good rifle... stack masking tape on the back of a cartridge until it just barely allows the bolt to lock... compare to unknown rifle...should feel the same. Add another layer of tape and it becomes a "no-go". It should not lock down in the good rifle, and also not in the in question. My kit had matching numbers and this was just for reassurance before I let it go bang. Learned this a few years ago on this forum. |
Never trust the headspace on a used rifle untill it has been checked. Masking tape is like playing Russian roulette. I don't care how many experts on the internet say different..Pat |
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"Never trust the headspace on a used rifle untill it has been checked. Masking tape is like playing Russian roulette. I don't care how many experts on the internet say different..Pat" Pat? I totally agree with you. Given the very low cost of HS gauges vs an Emergency Room visit? The "tape trick" is a lot like saving money on Pacemaker batteries by buying "Heavy Duty's" at the Dollar Store :) I'll add: I've had TWO NEW Sar2's, as well as three matched kits, fail a NOGO check. In all cases? The rifles were restored to minimum HS with new bolts. I now check EVERYTHING on receipt. |
I like how you think 
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