ar 10 6.5 creedmor

[labradoodle]

I had a bad gun smith build me an ar 10 in 6.5 creedmor.

it will not strip the first round off the mag and go into battery. if you drop the mag pull bolt half way back a let go it with lock up. stays lock back with the last round and cycles though the mag fine.

so far with factory ammo 120 grain ammo ( I know not the best) it was holding a 10in plus group at 100 yards. With my bolt gun I can get .25in groups. I know the gas gun won't do that but it should be better.( I handled for the bolt gun)

the bolt carry is just a cheep no name I can steel bare steel. would it be worth it to upstage to a jp system for the bolt carrier and buffer spring.

it has an 18in Krieger barrel

what else should be look at to fix this gun. I want to try to shoot it a mile.

 

[WhiskeyBiscuits]

Where do it hang up when the magazine isn't inserted? Are you seeing any marks on the barrel extension from the bolt hitting the lugs?

 

[labradoodle]

it takes the round half way off the mag. thought it wasn't oil enough so took the bolt carrier apart will put back together same problem

 

[Murdy88]

Could be a burr on the feed ramp cut of the barrel lugs. Doesn’t take much to have issues. Not sure if an AR 10 has two feed ramps like an AR 15 style, if it does, could just be the right or left ramp has a burr that’s catching the bullet or case.

If it’s just the first round in the magazine that could make sense.

 

[West.mass.hunter]

I had feeding issues with both of my ar10's. I built both m top to bottom with aero precision parts minus the triggers. 308 and 6.5cm. With pmags they wouldn't feed or cycle at all. I bought a D&H tactical steel mag and ran boxes and boxes through both arms without any issue. Bought 7 more D&H mags after that.

 

[labradoodle]

I have put 1200 rounds though it I was at a class and had to use the gun it did it every time only on the first round

what would make the accuracy that bad

 

[Murdy88]

If there is a burr catching the bullet, it could scrape bits off it or even shove the bullet deeper into the case causing loose headspace.
I’m not familiar with AR-10s but some ar-15 barrel will have the ramp issue and I know an AR 10 buffer spring is powerfull enough to shove a 9mm bullet further back into the case if it catches on the feed ramp.

 

[labradoodle]

I use lancer mags don like p mag

when I pull the round out no damage or marks

 

[Murdy88]

Something is definitely wrong with that accuracy. Even on cheap ammo in a cheap barrel that’s real bad. Might be best to take it by a gunsmith to check it out. Sorry but my knowledge is limited on this. You have a pic of the round jammed up?

 

[LeftyWilbury]

AR10s are finicky beasts. gas issue can make cycling problematic. i had to open up gas ports on both my AR10 ballistic advantage barrels to get enough gas to reliably cycle. then adjust accordingly with adj gas block for suppressor use. 10" groups sound like something is loose. scope mount. bad scope. good luck

 

[jimh406]

I'd visit an AR forum. They'll probably tell you how to fix it. Probably needs a new trigger or adjustment. Otherwise, sell the gun and buy a Ruger SFAR.

 

[WhiskeyBiscuits]

Could be a burr on the feed ramp cut of the barrel lugs. Doesn’t take much to have issues. Not sure if an AR 10 has two feed ramps like an AR 15 style, if it does, could just be the right or left ramp has a burr that’s catching the bullet or case.

If it’s just the first round in the magazine that could make sense.

That's what I'm thinking too. Over torqued barrel nuts are common with AR style rifles. There'd be evidence of the bolt striking the barrel extension.And yes, anything that accepts a double stacked magazine will generally have 2 feed ramps.