Trouble shooting 6.5 grendel in AR-15

Kaitum

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I already picked @Mthuntr brain on this one. Figured I'd see what the rest of the group's thoughts are. I took my AR in 6.5 Grendel out for the first time today. I was shooting 123 gr Hornady ELD factory ammo. When I loaded the first bullet I noticed the bolt was fairly tight on closing. I squeezed the trigger....click. I pulled back the charging handle to eject the casing and it was hard to pull back. After some effort out pops the casing, primer unfired and bullet seated in the rifling. I didn't bring a cleaning rod with me (my bonehead move) so that was a quick trip for the rifle. I measured those bullets at 2.25" overall so they shouldn't be too long.

Any ideas on the problem? I'll call the company tomorrow to get their thoughts.
 
On the surface, it sounds like your bolt was out of battery, also indicated by the bullet getting pulled out of the case. AR hammer will not strike the firing pin unless the bolt is closed completely. Also sounds like you have something going on with chamber/ammo.

New factory rifle or build? Did you ride the CH or need to use FA to try and close the bolt?
 
On the surface, it sounds like your bolt was out of battery, also indicated by the bullet getting pulled out of the case. AR hammer will not strike the firing pin unless the bolt is closed completely. Also sounds like you have something going on with chamber/ammo.

New factory rifle or build? Did you ride the CH or need to use FA to try and close the bolt?

New factory upper and lower (different companies between the two). I had to ride the CH to close the bolt. The upper doesn't have a forward assist.

I have some 123 gr Hornady SST factory ammo I can try. Haven't seen any other ammo in lighter weights lately to try shorter bullets.
 
Throat is too short. Every now and again a company will get a reamer that's ground incorrectly. The compound leade is difficult to grind.

What make is the upper?
 
Looks like riding the CH can be part of the problem so I'll avoid that next time and try different ammo.
I didn't think of this but if it's leaving a the bullet in the rifling then I'm still thinking it is short throated. I hope a call helps out.

I have a BCA upper with a side charge that I got on the cheap shortly after you did Kaitum. I don't have ammo on hand yet and I guess I need to measure then chamber. I just got a grendel modified case for my comparator so we'll see tonight what clues I may have. I knew BCA was as budget as a budget can get and have read mixed reviews but I gambled on a complete sidecharge upper for less than $200 trade value
 
Buckle up for the ride with BCA customer service. Exact same issue that I had with mine… did they send you the same barrel? Only took me about 3+ months to get an operational upper in after I ordered it…

 
So Kaitum and I have been having the BCA curse. We have been talking about the atrocious quality control even for a cheap company.

My upper was overgassed and pierced primers. Upon deeper investigation I discovered the barrel looked like a small child operated the tool when cutting the rifling. BCAs plan was to exchange the upper and not fix it.

I received the upper in maybe 10 days (weather delayed delivery). I cleaned it and slapped a scope on it and went to the range. First shot on paper at 50 so I walked to 100. Second shot almost same place. 3rd shot click...failed to eject and a crushed empty with a live round wedged in. Ok no problem and go to fix the jam. Fire round, no brass on the ground. Jam again with ruined brass. Ugh single feed, some eject some smashed. Ok it shoots 2" groups with Hornady ammo.

Anyway, I take the fore end off and discover the gas block isn't a pined block but a screw on one and the screws were loose eg the gas block wasn't actually attached. It may not fix the accuracy issue but it may solve the cycling issue. Will send upper back for a refund if I can't fix the cycling issue.

Here are some pics of the bore of the original BCA upper
20220306172812.jpg
20220306172740.jpg20220306172746.jpg20220306172705.jpg20220304162954.jpg20220304162557.jpg
20220307_171105.jpg
 
May be better off getting another barrell vs dealing with the factory. A good barrell can go a long way towards making up for a mediocre upper
 
May be better off getting another barrell vs dealing with the factory. A good barrell can go a long way towards making up for a mediocre upper
That's the next step. I'm in no hurry to spend $ on this upper so if I can get it to shoot without destroying brass (by fixing the gas block issue) that will suffice for right now...lots of barrel manufacturers that seem to have good reviews and I'm saving some fun money for trips this summer. I'll likely wait until all the draws are complete so I can afford toys with my refunds 😅
 
The pierced primers could be from excessive firing pin protrusion. Check your extractor against a case too, they're bad for only contacting on the corners of the ex. so it just slips off the case. If you have the gas block off measure the gas port and see if it's in spec.
As an added bonus, I've seen a lot of BCAs with crooked chambers
 
The pierced primers could be from excessive firing pin protrusion. Check your extractor against a case too, they're bad for only contacting on the corners of the ex. so it just slips off the case. If you have the gas block off measure the gas port and see if it's in spec.
As an added bonus, I've seen a lot of BCAs with crooked chambers
The pierced primers was the original upper and was apparently their excuse for the issue since i also got excessive signs of pressure like ejector marks and brass flow into the bolt. They replaced it with one that won't eject spent brass completely. The gasblock on the new upper was not even tightened down so that could have helped with the wonky ejection issues

Thanks for the tip on the gas port. I'll check that when I get a chance.
 
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