Stuck Brass

[Crews]

I had a piece of brass get stuck in a chamber and not extract this weekend, and wanted to get some advice from the group on what kinds of factors can contribute to a challenge like this.

I assembled the upper myself. Bolt was purchased with the barrel, and I am fairly confident that the barrel was installed in the receiver properly.

So what are the common reasons for a failure to extract brass?

 

[XLR308]

A barrel that has been nitride treated and the chamber not completly cleaned can cause brass to stick or short stroke the carrier.
I'm guessing you have allready looked the extractor over really well and checked fit with a case with the bolt removed ?

 

[sam4886]

Factory or your ammo?

 

[antithesis]

Fairly confident as in you check the headspace with go/no-go and know, you did not check but think it is good?

 

[Crews]

To answer some of the questions:
Fairly confident in assembly means I put the barrel in the receiver and torqued the barrel nut properly. But I don’t know how to check the extractor for function, and I did not check headspace. In my ignorance I was hoping I could get by with buying a bolt matched to the barrel. It’s a 12.5” ARP 6.8 with super bolt.

I am definitely using factory ammo.

I shot it 5 times to zero optic and make gas block adjustments. I did notice that my SLR bottomed out at the lowest setting, with plenty of gas left to run the bolt and lock back on an empty mag. On shot 6, brass stayed in the chamber and the extractor ripped the case rim off.

 

[XLR308]

To answer some of the questions:
Fairly confident in assembly means I put the barrel in the receiver and torqued the barrel nut properly. But I don’t know how to check the extractor for function, and I did not check headspace. In my ignorance I was hoping I could get by with buying a bolt matched to the barrel. It’s a 12.5” ARP 6.8 with super bolt.

I am definitely using factory ammo.

I shot it 5 times to zero optic and make gas block adjustments. I did notice that my SLR bottomed out at the lowest setting, with plenty of gas left to run the bolt and lock back on an empty mag. On shot 6, brass stayed in the chamber and the extractor ripped the case rim off.

Melonite treated ARP barrel, if you haven't allready give the chamber a thorough cleaning with Hoppes 9 or whatever solvent you prefer and give it another go.
The first ARP 6.8 barrel I bought I just wiped out the chamber and bore and went to the range, had issues with sticky chamber and brass had a smoked look to it from the residue left over from the nitride process.
After a thorough cleaning it has been flawless since.

 

[Danale147]

If you're still having problems after cleaning the chamber really well, look into the possibility it is overgassed. The brass may not have time to shrink back down before the bolt begins to cycle back and the extractor comes off the rim of the case, leaving it in the chamber. Had this issue on a couple semis

 

[Crews]

Melonite treated ARP barrel, if you haven't allready give the chamber a thorough cleaning with Hoppes 9 or whatever solvent you prefer and give it another go.
The first ARP 6.8 barrel I bought I just wiped out the chamber and bore and went to the range, had issues with sticky chamber and brass had a smoked look to it from the residue left over from the nitride process.
After a thorough cleaning it has been flawless since.

I thought about a dirty chamber, thanks for the confirmation. I will admit I was too lazy to clean the barrel out of the box before shooting it. I’ll definitely try to clean it up some.

 

[Crews]

If you're still having problems after cleaning the chamber really well, look into the possibility it is overgassed. The brass may not have time to shrink back down before the bolt begins to cycle back and the extractor comes off the rim of the case, leaving it in the chamber. Had this issue on a couple semis

I’m using a full weight carrier and an H2 JP SCS. I find it kind of odd that the gas block was almost closed and there seemed to still be a lot of gas. If this is still happening after I clean the chamber out I’ll take the suppressor off and see what that does.

 

[Danale147]

I have heard of some issues with the SLR blocks, they work most the time, but can have issues with certain components it sounds. From what I know, if the block is fully "closed" or tightened down, it should cut the gas off. Try all the easy fixes first and see where that gets.

 

[Crews]

Yeah in all fairness they all get gummed up and fail at some point. And this block has been used on two previous barrels and lots of rounds with zero maintenance.

 

[fanninland]

Interesting.. I have same barrel/bolt/gb (ARP 12.5" 6.8/superbolt/SLR) shooting suppressed with about 300 rounds down it and have been having same extraction issues lately. I do clean and even polish ARP chambers ( I've built 8 or 10 ARP barreled uppers) with flitz on 20ga mop chucked on drill before assembly due to the melonite treatment. While chambers may initially be a little tight they smoothed out with use. However this barrel, which shoots like a laser, has become seemingly worse lately . I'll get almost through a 15 rd mag on a sounder of hogs before a fired case fails to extract. Clean the chamber good with Hoppes and it'll shoot another 10 or so rds before case seizes up again .

I haven't thought about it being over gassed. I am usually shooting at night with a brass catcher so haven't checked ejection pattern, but I'll do so now. A deteriorating gb might explain why this issue seems to have slowly gotten worse. Anybody have any other ideas I'm all ears - thanks.

OP - regarding headspace - FWIW if you purchased barrel & bolt from ARP at the same time Harrison usually checks headspace before it ships.

 

[Crews]

I’ve been too busy to get out of town and shoot this rifle again, but I’ll certainly follow up with results.

 

[Crews]

Spring hog hunting season is back in full swing, and I'm continuing to have challenges with stuck brass in this chamber. It's particularly bad if I shoot 10-15 rounds then leave the last bullet in the chamber. Next time I go to shoot it, I'll have a failure to extract that requires a cleaning rod from the muzzle to knock it out.

After this past weekend, I even left the chamber empty overnight and reloaded with a clean shell in a cold chamber on Sunday morning before I went home. Monday morning I had to bump the stock on the ground while pulling on charging handle with both hands to get the round out. The clean brass was corroded and nasty looking.

I talked to Harrison, he wasn't surprised by this and advised that I polish the chamber with Flitz. I haven't done it yet, will soon. Hope it fixes the problem. My only hesitation is that I've never had problems like this with any other barrel or caliber. I know ARP barrels are supposed to be one of the best for 6.8 but dang this is a lot of hassle. Even if I get this thing to work, I won't be buying another one.

 

[hlee]

Melonite treated ARP barrel, if you haven't allready give the chamber a thorough cleaning with Hoppes 9 or whatever solvent you prefer and give it another go.
The first ARP 6.8 barrel I bought I just wiped out the chamber and bore and went to the range, had issues with sticky chamber and brass had a smoked look to it from the residue left over from the nitride process.
After a thorough cleaning it has been flawless since.

This was my experience with an ARP 224 Predator barrel as well.

 

[bfoosh006]

Do you have photos of the fired brass ? ... And of the loaded but not fired round ?

 

[Merle]

I had a light weight ARP nitride treated .223 barrel once. 100 yard groups looked like a shotgun pattern no matter what ammo I used. I was able to off load it during the post Sandy Hook nonsense to a dude that didn't care. Kinda soured me on the brand.

 

[Crews]

I just spent the last hour polishing the inside of my chamber with a wire brush wrapped in patches, coated in Flitz and chucked up in my cordless drill. This is what ARP suggested I do when I called about this issue.

I am already a bit irritated, as this has never been a necessary step to make any other barrel work. Sure hope this doesn’t cause me any down time. Will update.

 

[hlee]

The first outing with my ARP barrel I had to mortar the first cartridge out of it. It went like that for about the first 6 or 7. Then, it would cycle enough to break the case free of the chamber, but not to cycle. By the end of the range trip, about 40 rounds, the rifle was mostly cycling, but not well. This was compounded by too much buffer weight with a +2 gas setup. Went back out with a lighter buffer and it ran like a top. It's only been out those 2 times, as I'm working through some other reloading projects, but I'm pretty happy so far. The 224 predator is a wildcat, so I signed on for a bit more pain than average. I did not polish the chamber...

 

[Crews]

Do you have photos of the fired brass ? ... And of the loaded but not fired round ?

Here’s a picture of one of the stuck live rounds I had to mortar out this morning. Before this was taken, I did end up polishing the chamber as best I could with Flitz. I didn’t have any failure to extract, but didn’t do a whole lot of shooting to get the barrel all that hot either.

 

[Merle]

Here’s a picture of one of the stuck live rounds I had to mortar out this morning. Before this was taken, I did end up polishing the chamber as best I could with Flitz. I didn’t have any failure to extract, but didn’t do a whole lot of shooting to get the barrel all that hot either.

I'd hit up the owner of ARP. He posts fairly regularly here. Goes by the name Constructor I do believe.

 

[hlee]

Here’s a picture of one of the stuck live rounds I had to mortar out this morning. Before this was taken, I did end up polishing the chamber as best I could with Flitz. I didn’t have any failure to extract, but didn’t do a whole lot of shooting to get the barrel all that hot either.
View attachment 7283074View attachment 7283075

Looks like it was salvaged from the Titanic. What did it look like before it went into the chamber? How long was it there?

 

[Crews]

Yeah I’m at the point where I think I’ll yank this barrel and send it in to him. I’m sure he’ll take care of it. He’s got a pretty good reputation.

 

[sam4886]

That case is the ugliest thing I've ever seen. No wonder they are sticking. Try with a nice, clean, new round and I bet you won't have problems.

If it was clean going in, then you need to clean the living shit out of that rifle. Even the bullet has shit on it....

 

[Crews]

I’m shooting 100% suppressed, so the rounds are never going to be spotless loading out of the mag. I will say rounds sitting in the mag don’t get any dirtier than my other 300blk SBR?

 

[Snuby642]

Were those rounds stored in salt water or battery acid.

Nasty looking.

Had my son store fired brass in steel ammo cans long term that looked like simmilar corrosion.

I started using car wax in my dry tumbler media, no corrosion or even tarnish since.

Guessing ss wet tumbled super clean brass could end up like that.

Has anyone dry tumbled loaded ammo?

 

[Snuby642]

Looks more like corrosion than gsr to me?

 

[Crews]

All brand NIB shiny factory ammo when it goes into a mag.

 

[Snuby642]

No argument intended but that is corroded.
How long was it stored in the steel mags?

Not bent on arguing ammo brands or the like but I have ammo over 5 years old
with no corrosion and my reloads over a year old without any.

If you were to clean a handfull with? Scotchbrite and see what happens.
In a tight chamber that could be a problem.

I have read about people tumbling handgun ammo after loading not sure if safe on rifle.

 

[Snuby642]

Galvanic corrosion.

 

[Crews]

Again, there is zero external corrosion on these rounds before I use them. We’re talking brand new boxes of factory ammo. No storage, no saltwater, no nothing like that. Thanks for the thoughts but this is barking up the wrong tree.

I’ve had lots of SBR’s, and used every one of them exactly the same. I’ve never had an issue like this before. I should be able to shoot my gun, leave a round chambered, put it on safe, and trust it to work properly the next time I pick it up. It’s not an unreasonable expectation.

 

[supercorndogs]

Galvanic corrosion.

Galvanic corrosion - Wikipedia

en.wikipedia.org

Its not galvanic corrosion. It is a process that happens between two metals, not metal and air.

My ARs do the same thing if you shoot a few out of a mag. I imagine its left over bore solvent that get blown back into the action.

OP. Have you confirmed head space with a HS gauge.

 

[Crews]

Galvanic corrosion - Wikipedia

en.wikipedia.org

Its not galvanic corrosion. It is a process that happens between two metals, not metal and air.

My ARs do the same thing if you shoot a few out of a mag. I imagine its left over bore solvent that get blown back into the action.

OP. Have you confirmed head space with a HS gauge.

no sir. Bought bought bolt with barrel from ARP and assumed it was gtg.

 

[hlee]

I know you want this gun to run 100% suppressed , but you might be better off starting without the suppressor. Get the gun running, then add in the suppressor.

 

[supercorndogs]

If its sticking unfired factory ammo in the chamber. I would check headspace first of all. I have never checked or had a problem just throwing a barrel and bolt together, but it happens.

 

[Snuby642]

Evidently my eyes are getting old.
@supercorndogs
Has straitened me out and it's not corrosion.

It would be nice to know what that virus looking case rot is.

And wonder if it is contagious?

A list of gun solvents that could cause that would be nice. I have been lucky and managed to avoid them.

I sincearly hope none of that rot gets into a suppressor.

Ultimately it seems my 34 years of basket weaving has been a waste, darn.

 

[clcustom1911]

I just spent the last hour polishing the inside of my chamber with a wire brush wrapped in patches, coated in Flitz and chucked up in my cordless drill. This is what ARP suggested I do when I called about this issue.

I am already a bit irritated, as this has never been a necessary step to make any other barrel work. Sure hope this doesn’t cause me any down time. Will update.

Short cleaning rod, drill, Chamber brush, wrap with patches, put fine fine lapping compound, like 800-100p grit, on the patches. Insert chamber brush into chamber, spin with drill for 20-30 seconds. Clean out chamber.

Fire away. Melonite tends to microscopically rough up the surface finish underneath, even on mirror finishes.

I've had 2 melonite barrels from 2 different manufacturers that, even when gassed correctly (factory ammo casings ejecting 90 degrees to my right) would still get a casing stuck every once in a while. Polished the chambers, et voila. Fixed and awesomeness followed.

 

[bfoosh006]

@Crews



I fully accept your NIB ammo comment... but something is corroding your brass and copper bullets.

That blue green corrosion is "classic" "brass corrosion.

I can't say I have seen that happening so rapidly / thoroughly corroding NIB brass. ( 35+ years of reloading and shooting, Oorah )

What / or how / with what, are you using when cleaning your suppressor ? ( Maybe something internally is blasting into your upper )

And I suggest you take apart a few of the rounds and look at the powder inside of that specific ammo... clumped ? , stuck together ? , compressed ? Smelly ( breaking down ? )
Look at the bullet bases of the pulled apart rounds.. for corrosion.

What lube ? ( maybe producing corrosion ? )

At the very least... try some different OEM ammo... and hold off firing those other rounds... just in case they are "bad".

We all know , Those corroding cases are not going to help your firearm cycle.... tapered cases ( 7.62x39 ) might tolerate that corrosion, and operate ( far less force to extract )

Combine the failure to cycle, and that resulting corrosion... and your ammo may be "compromised" some how at the powder... and that "could be" dangerous if the powder is maybe breaking down.

IE.... better safe then sorry.

Something in your setup is producing / causing odd corrosion.

I strongly suggest you check your suppressor as well... that corrosion is most likely in there as well.

Pics of the bolt carrier ?

 

[Crews]

The ammo is Hornady 120SST ammo. I usually buy it a few boxes at a time from various Academy stores during my travels. So same ammo but from many different lots.

It is an interesting conversation, I haven’t thought about it from the corrosion perspective just yet until everyone brought it up. I know the brass is 100% spotless until it gets loaded in the mag. From my loaded/used mag you can actually see the corrosion starting. With a suppressor I’ve always seen rounds in mag get carbon/powder residue; but come to think of it never seen corrosion like this.

Once it’s loaded into the chamber it gets much worse. Is this just a continuation of the process started in the mag, or is there maybe some condition in the chamber that is accelerating it?

I don’t clean my can, ever. The receiver/BCG gets cleaned with a normal CLP then lubed sparingly with motor oil. The barrel has only been cleaned a few times, and only because of this issue. It’s not like a have a bunch of crazy solvents sloshing around in there?

 

[Crews]

I do have a case of Hornady Black coming in next, with the 110 HPBT bullets. I wonder if they use the same powder in those as the SST’s?

 

[Snuby642]

Just a piece of advice from an old guy, not a fudd.

I was born in the 1950's been shooting and cleaning guns since the 1960's.

FLUSH ALL THAT SHIT OUT OF YOUR GUN AND CAN ASAP.

Whatever the combo of stuff it is that eats brass that quick is not good for your barrel or suppressor.

Get yourself a standard brand and use that. Being old of course I suggest Hopes since I have never had a failure due to them.

Not to argue that there are not better products but seems you are not any better at finding them than I.

Quit f-ing around before you toast the barrel and can.

 

[bfoosh006]

Wait.... those corroded rounds in the mag... those were ONLY hand loaded into the mag. ( IE never inserted into the firearm, strictly and ONLY loaded into the mag

And that mag was not inserted while you fired a round ?

I had "assumed" that the rounds in the mag were after a round had been fired.... since the top 2 appear "more" covered in corrosion, the 3rd one looks "less" covered.

And I could see where one of the rounds had been stripped away ... ( might have been wrong)

If those rounds were loaded into the mag ONLY ( not the rifle ) .... where are those mags stored ? .... In Web Gear ?... maybe soaking wet at one point in time web gear ... then put away not fully dry ?

Leather used to be notorious for this kind of corrosion.... with it snug fitting loops holding revolver cartridges... retaining moisture closely to the cartridge surface. ( part of the reason for nickel plated cartridges )

 

[Crews]

The corrosion on the rounds in the mag is happening while the rifle is being fired. Not before, or after.