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Posted: 9/26/2015 3:54:05 PM EDT
I was helping a friend with his 10.5 blackout build. He has probably only fired 30 rounds with it. His problem is each time it fails, the round seems to be extracted from the chamber, but it doesn't eject and the new round jams the fired case up into the roof of the upper (and ruined the case). it fails about 70 pct of the time. It locks back on last round fine. Below is a picture of one of the failures.
I took it to the range today with my guns so i could switch out pieces. When i replaced the BCG with mine it functioned flawlessly. What do you think the problem is? Is the extractor just letting it loose too early or something with the ejector? One last thing is i was looking at the bolt face of his Spikes 556 BCG and it looked much larger than my LMT. Is that a problem? i looked on Spikes website, but it doesn't look like they make larger caliber bolts. 
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300 Blackout uses standard 5.56mm bolts. The one on the left is a 6.8SPC, 6.5 Grendel or a 7.62x39mm bolt. Your friend purchased the wrong bolt or was shipped the wrong bolt in error.
Bullet weight, powder selection and charge weight makes all the difference when trying to get 300 Blackout up and running. Heavy bullet sub-sonic loads will rarely function in a semi-auto. AA-1680 is probably your best option when running the heavy weight bullets around 1000 fps. |
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Quoted:
300 Blackout uses standard 5.56mm bolts. The one on the left is a 6.8SPC, 6.5 Grendel or a 7.62x39mm bolt. Your friend purchased the wrong bolt or was shipped the wrong bolt in error. . Yep, even a quick look at the bolt on the left brass ring mark left by the spent brass is screaming that the bolt face recess is too large brass being used, and why the extractor is slipping off the rim on the spent case pull to leave the spent case in the action. |
| Thanks, yeah i thought that was too large. Yes, a 556 bcg was purchased from primaryarms but they must have sent the wrong one. I contacted the friend and he just asked me to buy another 556 bolt and not worrying about returning so i guess i'll end up putting the 6.8 (or whatever it is if i am able to find out) on EE. |
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