Finally got around to assembling my AR10 using PSA assembled upper and PSA stripped lower and parts kits. Jamming up from the get go…Bolt stays open on empty magazine…It extracts empties but doesn’t eject them and they jam up with next live round…any ideas? Thanks
Post some specifics:
Ammo used?
Adjustable gas block?
Did you lube it good?
Buffer and spring combo?
Edit: pics would be helpful also.
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originally tried steel cased Tula, but tried brass cased too.
Fixed AR style gas block
Bought kit with assembled upper and lower parts except lower receiver, which I also purchased at the time. Buffer and spring and everything else are original to the kit.
It sounds like your bcg is not going all the way rearward to eject. So let’s take a hard look at the buffer. For 308 AR’s there are two styles. A shorter one that is used if you have a collapsible stock and a longer one for fixed stocks. Can you tell me which stock you have?
Edit: some steel and brass can be underpowered. Also, did you lube it good? AR’s are meant to be run wet and that will solve many issues.
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Try this also: remove the bcg and slide an empty case under the extractor. Does it move freely? Does the extractor move also? If everything is too tight you may need to dissamble to make sure no junk is stuck in there.
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I have the same issue. How did you fix this?
@joe66mustang give us some specifics…which ammo, buffer, spring, build specs (factory or homebuilt)?
i have a gen 2 psa ar10
stock buffer
stock recoil spring
extra power extractor spring
adjustable gas block.
ballistic advantage modern series barrel.
the issue im having is the bcg will move too quickly rearward and the round hits either the ejection port or the deflector and reenters the chamber.
i added the adjustable gas block shut off the gas and slowed added gas until the rifle locked to the rear on an empty chamber.
the issue still remains. however it does happen less often then before.
I purchased the oden works adjustable buffer weight.
My next idea is a extra power buffer spring .
Any ideas would be welcome.
You need to add more buffer weight or an extra power spring. Wolff makes the best recoil springs.
And stop closing your eyes when you pull the trigger. 
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with one round in the chamber, where does the shell eject? should be between 3-430 on a clock face
I am planning to shoot this rifle in next day or two, I’ll get back with you. Thanks
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Yes just load one round of the mag observe where the round ejects if the Bolt locks back. Let me know the outcome before you get caught up in the buffer/spring circus.
I had this issue with a factory built original DPMS LR308, and pulled my hair out, and ultimately upon the advice of a few people on another forum they had me take the bowl down and look for any rough spots in the machining which I found a little bit of machine marks which I use a little emery cloth on, and then oiled the living ■■■■ out of it.
Large format AR‘s love to be wet with oil and that and the little rough spot on the bolt was the fix, so I threw it back together and never had a problem since.
people right out of the gate said he need this buffer or that buffer or an adjustable block and so on and if I want to doing that without a few simple test prior I have compounded the problem and probably still be trying to figure it out.
That said are using a carbine or rifle tube? and what is the length of the buffer and the spring you used, and are they for the AR10? The AR15 stuff fits but will work.
There’s absolutely no reason whatsoever why that rifle shouldn’t cycle with a standard buffer and spring, and fixed gas block, which if you haven’t done yet you should check for alignment and tightness.
In addition to my DPM S, I also have the exact same PA10 as you do and it functions flawlessly with all the standard parts and has since now.
The ejection pattern is going to Reveal our first clue. While you’re out there also try it with a couple different magazines.
Send me the buffer/spring specs and which stock before you shoot to rule that out before you shoot
Well said it’s almost boggling how much oil large-format AR’s like
added 5.4 buffer
tube is 7 5/8
spring is 11 inch n 28 coils.
Just went through the same thing a couple of weeks ago. I found that my ejector was frozen. It didn’t want to move. I went out and bought a different bcg. Problem went away. Since then I worked the ejector on the original bcg by just taking an empty case and pushing it in and out until it worked as it should. Before I could take the empty casing and insert the rim under the extractor and seated it. I could shake the bcg and the casing would not fall out.
My 6.5 PSA AR10 does the same thing, doesn’t matter what the gas block is set on. I’ve tried it from full closed to fully open with no improvement.
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changed the ejection spring and extractor spring. slowed the cycle way down with a gas block and buffer weight. problem went away.
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To the OP… I was looking at Info for a Gen3 AR-10 on YouTube two nights ago and I came across a Video where this Gen2 Lower owner was having issues that included Mags simply dropping out for No Commanded reason.
PSA Customer contacted Customer Service and he gave them the Serial Number of his Lower and Customer Service said they had identified batches that were found to be Out of Spec and immediately shipped him a Complete Gen3 Lower with all the Bells and Whistles , 2nd Day Air no less.
Its a reach… but its worth investigating.
The ejectors seem to be working properly, I can hook a round under the extractor and rotate it into position and the push it around easily. The only problem I can see is that the bolt has tooling chatter marks that even leave marks on the fired primers looking like a plus (+) sign. I think the chatter marks may be interfering with bolt rotation.
I doubt that is interfering with rotation.