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Posted: 2/20/2013 11:09:35 AM EDT
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Been reading the posts for a while and finally found an issue I can't fix myself. I bought a used DPMS LR-308 at a show last month, I know ya never know what your going to get but it was cheap, and I have been having issues with the bolt jamming. Not sure when it started because it works fine when it is fired, but its when manually ejecting the case that it sticks(even tried empty case). I can just tap it with a mallet and it opens fine. I notice the case is getting chewed up slightly but not terrible. Looks like the previous owner shot Hot loads cause the bolt is slightly scared but the extractor look and seems to function properly. Ejector is a little rough but seems to function ok. As soon as I find a replacement kit that is not backordered I will have one. I have cleaned and lubed properly, removed barrel and a case slides in and out of the bore properly, tried several different factory rounds and reloads. The kicker is if ya shoot it it all works fine. It's only when pulling back the charge handle to unload. Could it just be a scared bolt and assembly?? Maybe wrong BCG?? The upper and barrel have no identifying marks on either so might not even be dpms. I thought all barrels were marked at least. The lower does say DPMS LR-308. If anyone has any thoughts or ideas, before bolt rebuilds get back on the market , they would be appreciated. Thanks Matt |
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Seems like you only have one issue.
On my LR308 build, the charging handle was very sticky to pull back. I don't need to hit with a mallet like you. I installed the POF roller cam pin and it was much smoother. It is about $30 dollars. Just my 2 cents. Is it only "jamming" with a cartridge in the chamber? Otherwise, it pull back smooth empty? |
| It sounds like an issue that has been discussed before. If you eject a round that had been chambered and it isn't deformed, a factory round can be dropped in the chamber and falls out by itself when the muzzle is pointed up and it functions properly when shot, it is probably a tight fit between the barrel extension and the bolt. You will only notice it when there is a round chambered. I had the same problem. After mine was broken in, the problem resolved itself. Just lube it generously, grease the contact surfaces of the bolt lugs and the barrel extension and have fun! |
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Quoted:
It sounds like an issue that has been discussed before. If you eject a round that had been chambered and it isn't deformed, a factory round can be dropped in the chamber and falls out by itself when the muzzle is pointed up and it functions properly when shot, it is probably a tight fit between the barrel extension and the bolt. You will only notice it when there is a round chambered. I had the same problem. After mine was broken in, the problem resolved itself. Just lube it generously, grease the contact surfaces of the bolt lugs and the barrel extension and have fun! +1, what he said... ETA: Although chances are it is due to things as described by 10-7, it might be good to just verify you don't have a headspace issue though. Just in case it isn't a stock DPMS arrangement. I had one that I just sat and worked by hand while sitting on the couch and watching TV for awhile. The first couple required a mallet on an EMPTY chamber even. I also wouldn't recommend using live ammo if you use a case. I seperated the upper, pulled the carrier about 1/2 inch back from locked position and whacked the back end of the carrier really stiffly with a plastic maul. It was easier to unlock the bolt w/ the upper seprated. I just whacked it backwards using a brass punch on the carrier notch on the underside. Mine came out of it after a dozen or so cycles. It has been fine since. |
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Quoted:
It sounds like an issue that has been discussed before. If you eject a round that had been chambered and it isn't deformed, a factory round can be dropped in the chamber and falls out by itself when the muzzle is pointed up and it functions properly when shot, it is probably a tight fit between the barrel extension and the bolt. You will only notice it when there is a round chambered. I had the same problem. After mine was broken in, the problem resolved itself. Just lube it generously, grease the contact surfaces of the bolt lugs and the barrel extension and have fun! Mine performed similarly. "Sticky" when manually extracting a round, but smooth operation of the bolt without a round. [10-7LEO, looking forward to the next range meet.  ]
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Quoted:
... I had one that I just sat and worked by hand while sitting on the couch and watching TV for awhile. The first couple required a mallet on an EMPTY chamber even. I also wouldn't recommend using live ammo if you use a case. I seperated the upper, pulled the carrier about 1/2 inch back from locked position and whacked the back end of the carrier really stiffly with a plastic maul. It was easier to unlock the bolt w/ the upper seprated. I just whacked it backwards using a brass punch on the carrier notch on the underside. Mine came out of it after a dozen or so cycles. It has been fine since. +1 Definitely easier to unlock the bolt this way! tkno- getting close to the start of the season, can't wait! |
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