Stag Arms .308 AR issues

I have a couple questions for you AR guys. I purchased an AR10 from stag arms back in December. I had issues right away shooting PMC bronze fmj’s with failure to feed. I emailed customer service and they recommended Lucas heavy duty gun oil, trying different ammo, and running the bolt carrier wet.

I took the gun to a indoor gun range and fired four different kinds of ammo with two different magazines and still had a pile of failure to feeds. Each time I’d have to manually load a round, it would eject the shell but not get the next. I ended up sending the gun back to Stag under warranty to be looked at.

I called them today and they said they are returning it and they couldn’t find any issues. The best answer they had is the guns like more expensive ammunition. Is this something you guys experience in your AR10’s?

I feel like a $1900 bare gun should cycle just about any ammunition you put in it.

Ammunition I’ve tried:

PMC bronze
7.62 (can’t remember brand)
Sig Sauer elite performance
Remington core-lokt


With two different Magpul mags

I can tell you your more expensive autoloading shotguns and 1911’s will require a break in period with quality ammo and magazines. Of course my AR10 is a DPMS and didn’t care what trash I threw in it.

If they couldn’t find an issue, ask what ammo and mags they used.

Is your gun capable of 7.62 and .308?

I’ve got roughly 200 rounds through it. Everyone told me they had a break in period. At an average of $1 a round I assumed that would be plenty to break a gun in. I could be wrong.


What is considered quality ammo?

Magtech 7.62 and the magpul magazine that came with it. That’s what she told me on the phone.


It is capable of both

Generally anything not Chinese, lol. I’m still thinking a magazine vs ammo though.

What is a better magazine than the magpul they issue with it? If they didn’t change anything on it I’m not expecting different results with the same mag and the rest of the shells I have left to shoot.

Sounds like a magazine issue. If it isn't the magazine then the magazine isn't locking up high enough. The only other thing it seems it could be is the bolt isn't cycling far enough back. Call them and if they fired it more than once verify which magazine and ammo they used. If they didn't fire it multiple times then send it back and tell them to do adequate testing to diagnose and fix the problem. A failure to feed issue is absolutely unacceptable in a $1,900 rifle.

From what I can find that PMC bronze is made in Houston, TX.

The current ammo shortage makes it hard to experiment with anything other than what’s readily available. I have access to PMC locally.

Try only loading the mag with 3 bullets.
Try half full.
Try a full mag.

Had a buddy that bought a VERY expensive AR10...in excess of $5K. He had similar issues and it turned out to be a magazine issue.

Just curious, does the bolt cycle with ease by hand?

Turkn I agree. They told me they fired 15 rounds using the magpul mag they sent with it and the magtech 7.62 bullets.

From what I gathered that’s what they considered suffice to say it’s good and ship it back.

The bolt does cycle easy by hand. At the indoor gun range the gentleman behind the counter gave me a different magpul magazine to try and it had the same issues. He recommended to send it back.

I had similar trouble with a BCA .350 upper. Sent it to them 3 times before they just replaced it with one that worked. I'd do the same with the Stag if I were you. Send it back until its right or replaced with one that is right or get your money refunded.

Thanks ADC!

That will be my plan if I receive it and cannot mag dump 10 rounds without an issue.

I'd go through at least two!

Sure another $20 plus bill out the barrel.


That’s just sarcasm, I’ll try a whole box.

At this point what's another $20?

You ain’t a kidding

I would put money the buffer spring is too long or has too much tension and or the detent is not sitting properly. I had similar issues on an ar I built, took it to a buddy who is a wizard with ar's. Within in 2 seconds the diagnosis was in once he took it apart he confirmed it cut off 2 coils from the buffer spring replaced the detent and spring and it shoots like a dream now.

My buddy said it's a very common issue with the buffer springs (all brands). He trims them often and it usually solves the issue.

I wouldn't be surprised if the buffer tube is being hit hard too. Post a pic of the buffer tube

My bother built a AR-10 and it didn't want to feed. He tried different brands of magazines and found one that worked. A well made, semi auto should function from the start. The only reason for a break in period would be to knock off rough edges that are hanging up.
I shot a new Benelli M-2 that would jam about 5 or 6 times to a box of shells. Everyone said you have to break it in. After about 60 cases of shell it was down to jamming 3-4 times a box. I finally was told to replace the spring in the stock with a stronger spring and that fixed it 100%. A different buffer and spring may help. Other than not feeding you have not said what it does. There are a number of things that can cause a semi auto to not feed. What it does can give clues to why. You should not have to replace parts on a new gun to make it function, but I have see where it was required.

check the gas block , some manufacturers have been making them so fast that the gas blocks didn't get tightened 100% I have had them work forward after some rounds , if it is leaking you should see it around the gas block soot around the gas block

if the gas block moves forward it partially blocks the gas port as well as bleeding of gas and not inserting the gas tube as far into the gas key as it needs to be

does it have an adjustable gas block?

remove your BCG , pull the cotter key, firing pin and cam pin. take the bolt out of the BC inspect your gas rings

make sure like you would on piston rings that the gas rings are not lined up that the notch is opposite the one before it. now use the oil they told you to get those rings wet and don't dry them off re-assemble your BCG


only one round in the mag to start

you lock back the BCG insert mag let it click in hit the bolt release let the bolt slam forward

fire.

does it lock back?

2 rounds , does it feed the second round ? does it lock back after the second round ?

if it feeds and works load a mag with 5 , fire it , load with 10 fire it does increasing the rounds in mag change feeding.

if you have done all this and there are still issues , you should call them again explain what you have done testing and ask for an RMA to send in the gun

Never played with an AR10, but had a 15 upper that would spit the empty, but not pick up a new round. I tried it on a different lower, changed bcg, and even played with the buffer weight with no difference. Turned out that the gas block was not lined up correctly and it wasn't getting enough gas to cycle the bolt all the way back. Not saying this is your problem, but another possibility. Best of luck to you and hope it is an easy fix, but for that kind of money you shouldn't be having to find a problem.

GreenCountyPete was quicker on the draw.

I think Turkn8 may have a good idea. Magazine not locking well. I have experienced similar trouble. My suggestion is push the magazine release button all the way in with a cleaning rod or some other kind of punch then on the other side of the gun the magazine screw will protrude tighten it up at least two turns and then test fire. Repeat the procedure until you determine if it's tight enough. This seemed to be a common problem I have found when a round wont strip off the mag. Hope this helps. Good luck.

My friend brought a new ar he bought the gas key was installed backwards, it ejected fine but never would feed the second round

pictures ?

how would it even eject if the gas key was backwards

https://www.brownells.com/schematics/dpms-panther-arms-/bolt-carrier-assembly-sid811.aspx

did you mean gas block?

Thanks for all the advice guys. They told me today they are shipping it back so I should have it by next week. I will do an update on here once I try some of these things and let you know the results.

1900 for a production parts gun? wow, last AR-10 I purchased was a PSA lower with a verioforce tactical longbow custom upper in 6.5 creed, total was 1100.00 total price! almost all feeding issues in a properly gassed AR is mag related.

Yeah unfortunately to get a lefty eject that’s the only company that I found that makes a .308

Dead on, first thing I'd do it check gas block alignment and gas tube, been there a few times, and everytime it was either a crappy gas block or misaligned.

Wouldn't you think the company making the guns would of checked on that, especially after he sent it back to them with feeding issues?

I think it's going to be a mag issue. AR's can be very fussy.

Check your gas tube assembly, had a AR 10, that was simpler to your problem. My rifle's, problem not enough gas, pushing bolt back to cycle a round, after 2/3 rd. Easy fix, close your gas off, readjust gas valve until 1 rd will reject. Then load 3 rds, and fire. If you get your rds., off, turn your gas back down until it wont cycle. Then slowly increase gas, until it feeds properly. Sounds alot like bolt is to slow, and catching your feed rd. It could be just the opposite also to much gas, and bolt is bouncing. Seen this in AR platforms, when reloading ,to hot of powder That's my experience, when AR's wont feed properly. Plus what you said, tried different mags and ammo. It's a factory built rifle and Stag are quality rifles, have several Ar's, with Stags part kits
ADC statement is dead on, loose gas port, I'm betting gas problem, plus these people who test fire are test fire, not builders, these company's are building and rolling them out

Put me in it's a gas issue camp.

Yr not resting it on the bottom of the mag r u?

you would also expect an answer like we put 20 rounds of brand X 150gr ammo through it without any issue , please try this and not just it likes more expensive ammo.

Have more than a few AR's have shot lefty all my life, no problems with RH eject, if I did would only own a 223 and a 308, would not know how awesome the 25wssm and the 458 socom is. carry on!

I shoot plenty of other right handed guns. I just thought it was awesome they made a lefty and that’s what I am.

No I’m not resting it on the clip.


Got the email today it’s been shipped from stag so I should get it next week.

buffer spring too strong.

Please update us on it then.

I agree, most feeding problems come from the mag. I would turn in the mag release another turn or more. And make sure the mag is as high up in the mag well as possible.

Could be the mags... cycle them one by one and see if if you get good results. if so change magazines.

Well FedEx dropped it on my doorstep last night.

Haven’t shot it yet but remounted my scope. The gun shop in town had mounted the rock river arms mount with the thumb nuts facing the ejection side. That way before didn’t allow the cover to flip all the way up.

I turned the scope around and essentially have the mount backwards from the way it was to keep those thumb nuts out of the way. I’m assuming that’s not gonna be an issue? It gives me more clearance to grab my charging handle now as well.

If it warms up a touch today I’ll fire 3 shot bursts and see what happens. I did tighten the mag catch probably 6 or 7 times and it seemed to suck the mag up real good.

A lefty...

Yes sir! I know a guy can shoot a “righty” but why not have a lefty.

Bought my son “lefty’s” as well. He complained about shotguns blowback the worst and can cycle a bolt much faster on the left.

Here's a Stag Arms Lefty in .223 w/Coyote Reaper attached. Works great! No problems

Took it out with a full clip and it fired all 10 rounds without an issue. I will sight it back in later today.


Still gonna be using up the PMC ammo I have for it. Hopefully the issues have been solved.

Good deal. Hope she works out for you without further issues.

Yes It did Jacob

Post a pic of the buffer and the detent.

Good deal. I hope its all straightened out.

👍 good.

Took it out and sighted it in at 100 yards.

30 rounds of PMC through it with one minor failure to feed. Spent shell fully ejected and half loaded the next where it gets stuck at an angle.

3 rounds of Sig Sauer performance rounds that I will hunt with. Shot flawless for those.

im having the exact issue with my Stag LR308 , one of the things they told me was the buffer spring , said they had a screwup where AR15 springs mistakenly were sent out in a batch of LR308 rifles

some breakin periods are necessary do to the gas systems on AR's need carbon fouling to seal the gas system , with that said every AR ive ever bought brand new ran flawlessly out of the box , i have 200 rds in this Stag LR308 and i cant string more than 3 cycles together before it trys to shove 2 rds at once , ejects fine , throws the spent shell 4 feet , no adverse marks or scrapes on spent cartridge

i should say i am sorry for reviving this old thread but OP's issue is a exact blueprint of what i am experiencing

i missed the part where you sent it back to them while waiting for reg approval for the forum , did they say what they did to resolve the issue , , im going to run another 40 or so rds today , and if i cant im sending it back for them to straighten out