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Discussion Starter #1
Took apart my LRB/HRA M14 the other day as I'd neither cleaned nor greased in some years. I'd gone hunting and noticed that when I went to unload the round in chamber at end of day (yeah I suk at deer hunting, haven't got one in about 10 years), the bolt would not roll over the receiver lugs and come out of battery. Fired round into one of my trees to unload. NOT a headspace issue, checked that at home, round was in speck as well, no signs on the brass of anything.

Once apart I noticed nothing but there is just a scoshe of sticking right as the lugs on teh bolt roll into battery. With the oprod and spring on it is only a slight stick, but on it's own I' have to apply some pressure to get it to go into battery, definitely wont go in with only gravity. Once in, it's not too tight and will close on a guage. My guess is it's needing lapped for smooth operation. Will just firing teh weapon a hundred rounds take care of it or should I send it to a smithy? Function is fine when firing live, bolt tossed an extractor once, but that was a commercial part. NO function problems other than couldn't unload the round last week. Never had this before and have greased all and has improved. Also will it fire lap with grease on teh lugs?
 

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Chamber may need some polishing. If its been sitting, could be a little dried up fouling, grease or even some rust. Id start there first...

If it used to work fine, the lugs should not require any further lapping, but anything is possible if you stripped the rifle completely. Things may not have gone back together the same way. The lugs need some grease too.

Op rod spring may have lost some energy, depending on how it was stored...
 

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Discussion Starter #4
nah, it's always had this slight stiction. fires and reloads fine, with grease it seems to be fine and this was the one and only time it failed to manually extract. I've had it about 6-7 years, but have only put maybe 50 rounds thru it. 4 kids and no time anymore to shoot. This is my 7th M14 platform. It's an early LRB, 13xx ser. # Will grease prevent fire lapping?
 

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Had the same problem when I built a 25 over the summer. Bolt worked great screwed the barrel in and it was hanging up a little just as you described. I lapped the bolt lugs a little more smoothed it out then finished reamed the chamber. You could try lapping I don't hunk it will have a huge effect on your headspace. Or if it functions fine when firing leave it alone. It's from the bolt face in close tollerance with the barrel would be my diagnosis.
 

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sticky bolt

If you will inspect the top right rail on the receiver that the right bolt lug drops over as it goes into battery, you might discover some finish wear on the receiver at the apex of the curve , I have had several that do that at this location....also check to make sure your bolt face is not interferred with by the barrel shoulder....look for finish wear or gouges on the very end of your barrel at the raised portion between 9 and 12 o 'clock....also on the rounded portion of the bolt which captures the cartridge at the same clock figures.
 

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Took apart my LRB/HRA M14 the other day as I'd neither cleaned nor greased in some years. I'd gone hunting and noticed that when I went to unload the round in chamber at end of day (yeah I suk at deer hunting, haven't got one in about 10 years), the bolt would not roll over the receiver lugs and come out of battery. Fired round into one of my trees to unload. NOT a headspace issue, checked that at home, round was in speck as well, no signs on the brass of anything.

Once apart I noticed nothing but there is just a scoshe of sticking right as the lugs on teh bolt roll into battery. With the oprod and spring on it is only a slight stick, but on it's own I' have to apply some pressure to get it to go into battery, definitely wont go in with only gravity. Once in, it's not too tight and will close on a guage. My guess is it's needing lapped for smooth operation. Will just firing teh weapon a hundred rounds take care of it or should I send it to a smithy? Function is fine when firing live, bolt tossed an extractor once, but that was a commercial part. NO function problems other than couldn't unload the round last week. Never had this before and have greased all and has improved. Also will it fire lap with grease on teh lugs?
Since grease helped, I'd start with a tilt test, look closely for any binding of the op rod in the op rod guide, op rod guide alignment, op rod rubbing the barrel. Then I'd reinstall the op rod spring and look for whether it's hanging up or snaking on the spring guide. Also, need grease on the op rod spring, a dab back at the spring guide connector, and a light coat outside & inside the op rod. If that doesn't nail the issue I'd try a different magazine. Feed lips can get bent up and interfere with bolt travel. A lap-in issue would be my last suspect if the bolt is closing fully on in-spec ammo with grease on the lugs, roller, and rails. Good luck.
 

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contact

Since grease helped, I'd start with a tilt test, look closely for any binding of the op rod in the op rod guide, op rod guide alignment, op rod rubbing the barrel. Then I'd reinstall the op rod spring and look for whether it's hanging up or snaking on the spring guide. Also, need grease on the op rod spring, a dab back at the spring guide connector, and a light coat outside & inside the op rod. If that doesn't nail the issue I'd try a different magazine. Feed lips can get bent up and interfere with bolt travel. A lap-in issue would be my last suspect if the bolt is closing fully on in-spec ammo with grease on the lugs, roller, and rails. Good luck.
This is a great point BD.....I just did one and felt the similar bind, and found it was sure enough hanging the op rod on the handguard, filed a little away and she stroked smoothly....thanks for bringing this easy fix up.....I completely forgot already and that was two days ago....then again, I can't remember what I had for breakfast this morning DI2
 

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Sure, no prob. I always hesitate to recommend destructive testing or invasive surgery until the maintenance and fitting bases have been touched.
 

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Discussion Starter #10
it's in teh bolt, all else functions perfectly. completely disassembled BUT the bolt in receiver. it hangs in a gravity test, goes to the end and then requires a push to roll over into battery. NOT a headspace issue, closes on guage just fine, just have to press past the hang, which is THERE withor without a guage. NO other parts on receiver but bolt and barrel
 

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Clean and check for interference on both bolt rails. Things like cleaning rag debris or any kind of cloth on the rails will sometimes cause a hangup. Also check for any damage to the receiver bolt rails at the point that your bolt sticks. A nick in the receiver at that point may cause a hangup. Finally check to see if the bolt is cocked at the point of hangup, if it's shifting sideways at that point you may have one of the above or a receiver with unusual wear. This last one goes back to the manufacturer for warranty work. Good luck, sometimes these things can be a bear to figure out.
 

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Discussion Starter #12
i'll just finish wth what I believe. at best it will firelap, at worst it's an out of spec LRB receiver. I KNOW it doesn't need cleaning. I suspect a bolt lap job or just shooting it in will fix it . Please everyone reference what I've noted. My real question is if it will firelap w/ grease or should I lube up the lugs w/ lapping cmpd and smooth it in? I'm really fishing for experience on if it could be slightly out of spec or not? I've elinated all suggestions. it doesn't do this w/ a TRW bolt, but it won't headspace either, too long a gap at that point.
 

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I doubt it will firelap, that could take a whole lot of rounds, maybe never. Just lap it, get it over with and it will either solve the problem or you can deal with the receiver problem.
 

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i'll just finish wth what I believe. at best it will firelap, at worst it's an out of spec LRB receiver. I KNOW it doesn't need cleaning. I suspect a bolt lap job or just shooting it in will fix it . Please everyone reference what I've noted. My real question is if it will firelap w/ grease or should I lube up the lugs w/ lapping cmpd and smooth it in? I'm really fishing for experience on if it could be slightly out of spec or not? I've elinated all suggestions. it doesn't do this w/ a TRW bolt, but it won't headspace either, too long a gap at that point.
Art Luppino has a method that I use sometimes, when needed, ...you can take fine grit lapping paste and mix with grease to put on it where needed and cycle to wear or lap in....might be quicker than fire lapping. All the usual don't go too far cautions included.
 
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