Riddle Me This: Worst Day with ARs in ... Forever

[Centuriator]

I've been shooting ARs for a very LONG time and today was, by far, the WORST day ever.

First, I had my KAC SR-15 fail to extract a spent cartridge. I had to use a rod to remove the cartridge. I figured it was under-lubricated, so I doused it down and moved on. More problems to feed and extract. Fail to fire, even though the primer was struck.

Second, I decided, better try another AR.... same damn thing, twice. My BCM. Same thing...rounds would not go "boom" and would not extract out of chamber after not going boom. I dropped the mag and could not extract pulling the CH as hard as I could. Had to hold on it and slam the buttstock.

So, two different ARs, same issues. Different mags, different ARs, same issues.

But...same ammo

The ammo was IMI M193, 55gr.

Ammo problem? That's the only thing I can think it was.

 

[Precision Underground]

If you have the exact same issue in two know good firearms using the same ammo..... Yes, it is safe to say it’s probably the ammo. if You have been shooting ARs for a LONG time surely you would know that.

 

[Centuriator]

If you have the exact same issue in two know good firearms using the same ammo..... Yes, it is safe to say it’s probably the ammo. if You have been shooting ARs for a LONG time surely you would know that.

No need for the attitude. I'm simply trying to work through the diagnostics on this issue and check my thinking.

 

[Precision Underground]

No need for the attitude. What's your malfunction?

Sorry. Over-oiled ejector spring causing erratic ejection.

 

[Centuriator]

Sorry. Over-oiled ejector spring causing erratic ejection.

It was definitely an extraction issue, not ejection. I can only think that I got a bad batch of IMI. Which is why I'm rather baffled since I would think the odds of a 'bad batch' of IMI is rather remote, so I was trying to analyze what possibly the mechanical malfunction could be, but since it happened with both my KAC and my BCM, and after I relubed both BCGs, I just have to think it is the ammo.

And yes, I have been shooting ARs for a long time and I've never had this issue before.

 

[Praeger]

If you have, or can borrow a FL body die (open top - no neck sizing), see if an unfired cartridge from the IMI batch will fit. If it binds, it could be improperly sized from the factory

 

[eddiemac]

I had a similar issue with a brand new SR-15 using IMI ammo and sent it back to KAC. They said it was an ammo problem and said not to use IMI ammo in their guns. The same ammo shot fine in my BCM but I no longer usd IMI as certain lots seem to run hot.

 

[Sixfivesavage]

You've never ran steel cased shit through it have you? Enamel in the chamber if you have?

 

[Centuriator]

If you have, or can borrow a FL body die (open top - no neck sizing), see if an unfired cartridge from the IMI batch will fit. If it binds, it could be improperly sized from the factory

It was almost as though the rounds were over pressured and the case was swelling up in the chamber causing extraction issues.

 

[Centuriator]

You've never ran steel cased shit through it have you? Enamel in the chamber if you have?

YES, in fact, I have and the ONLY other time I've had an extraction issue was after shooting the stuff, suppressed, for 100 round and then, I basically turned my AR into a "bolt action" rifle where I had to yank the CH to extract and eject every round.

So.....ok...ammo.

I just thought IMI was some of the "better stuff"

 

[Sixfivesavage]

It is better stuff but if there's still enamel from the steel in the chamber then it doesn't matter what you shoot out of it till you get that shit out, anything is gonna get gagged up and take a dump on you. I'd scrub the chambers well and the bolts and relube it, see how it does then.

 

[Greg Langelius *]

Use a 223 case gauge and eliminate the doubt.

 

[Jefe's Dope]

My first instinct is bad ammo. But IMI is 'supposed' to be A++ ammo.

What gas length system are you running?

Hot loads, tight chamber, over gassed.

Try a third AR of a different gas length.

 

[TimK]

Use a 223 case gauge and eliminate the doubt.

Yep, do this.

 

[Centuriator]

It is better stuff but if there's still enamel from the steel in the chamber then it doesn't matter what you shoot out of it till you get that shit out, anything is gonna get gagged up and take a dump on you. I'd scrub the chambers well and the bolts and relube it, see how it does then.

not to worry, been a couple years since I've shot steel cased stuff.

 

[Centuriator]

My first instinct is bad ammo. But IMI is 'supposed' to be A++ ammo.

What gas length system are you running?

Hot loads, tight chamber, over gassed.

Try a third AR of a different gas length.

Not a gas length issue, I have thousands of rounds through the SBR and well over 2,000 with the KAC. No issues, until yesterday.

 

[lennyo3034]

All IMI I've ever shot was hot as shit. The only factory ammo I've blown and pierced primers with. Their 77 grain razor core was 2900 out of my 20" barrel.

 

[supercorndogs]

You've never ran steel cased shit through it have you? Enamel in the chamber if you have?

Steel cases do not leave enamel, lacquer, or polymer coatings in your chamber.

"If anything would make that lacquer coating “melt,” it would be the treatment these rifles received during the test. We shot them until they were too hot to hold – hot enough that a chambered round would cook off in ten to fifteen seconds. We also tried leaving rounds chambered before temperatures reached that point. None of this harsh treatment caused extraction problems.

We found no evidence to back up the claim that lacquer coatings melt in the chamber and cause extraction failures."

https://www.luckygunner.com/labs/brass-vs-steel-cased-ammo/#performance

 

[supercorndogs]

Yep, do this.

What Tim and Greg said. Grab a case gauge and measure them. We can all sit around play heehaw guessorama all day. First step of diagnosis, if its wont fit its in hole, measure it and see why.

I would guess a ammo problem just like you, but why leave doubt.

 

[Sixfivesavage]

Steel cases do not leave enamel, lacquer, or polymer coatings in your chamber.

"If anything would make that lacquer coating “melt,” it would be the treatment these rifles received during the test. We shot them until they were too hot to hold – hot enough that a chambered round would cook off in ten to fifteen seconds. We also tried leaving rounds chambered before temperatures reached that point. None of this harsh treatment caused extraction problems.

We found no evidence to back up the claim that lacquer coatings melt in the chamber and cause extraction failures."

https://www.luckygunner.com/labs/brass-vs-steel-cased-ammo/#performance

Good information. Never seen that before.

 

[spife7980]

I havent seen much IMI ammo, only a couple boxes on a couple different occasions but all of it that I have seen has been over pressure crap leaving nasty mangled brass behind.

 

[samnev]

I think it's an ammo problem as well. First I'd use a car length gauge on the IMI ammo to see if it's in spec. But as some have suggested see if extracted cases show any signs over over pressure.

 

[supercorndogs]

Good information. Never seen that before.

I was looking for another video where they were trying melt to the polymer coating off a steel case with a torch. I ran about 10k steel cases through a 7.62x39 ar15. I think carbon moving around a case, that does not expand as well as brass, sticks them. I started cleaning my chamber every 500-800 rounds and stopped getting a stuck case every 1k. It could have been the cases were too big and the and the later thousands of rounds didn't have any big cases in there too. I think it was the carbon though, because the less tapered 223 steel cases did it much worse.

 

[Centuriator]

Thanks for the feedback guys. I'm definitely convinced it was the ammo.

 

[crystalgold7mm]

Correct me if i am wrong( I know you will) but I believe IMI is a Nato ordiance manufacture. Their Match stuff is pretty good in most guns. The stuff I have shot was hot. Even though i have not reloaded any it looks as if their brass is much harder than american commercial brass. It will act almost like steel case ammo. Being at higher pressures it will give you erratic extraction on dirty chambers or wear a extractor spring out in a heart beat. Ar's can be finicky sometimes... Good luck.

 

[Centuriator]

Correct me if i am wrong( I know you will) but I believe IMI is a Nato ordiance manufacture. Their Match stuff is pretty good in most guns. The stuff I have shot was hot. Even though i have not reloaded any it looks as if their brass is much harder than american commercial brass. It will act almost like steel case ammo. Being at higher pressures it will give you erratic extraction on dirty chambers or wear a extractor spring out in a heart beat. Ar's can be finicky sometimes... Good luck.

Thanks for that input, I will thoroughly be cleaning both ARs and give them both a whirl again with the IMI and see what happens.

 

[Qazwsx]

I wouldnt shoot that ammo again, isnt worth it to confirm what seems apparent if you measured the ammo.

 

[NAS78]

Lot #?

 

[Unknown]

I would try some other ammo before I tried the IMI again. If the rifles both work well with other groups of ammo, and if malfunctions return with the IMI ammo, you know what it is. Whether it is that the IMI ammo is loaded too hot, incorrectly sized, over length cases, or some other issue with the ammo is largely irrelevant. If you know that ammo doesn't work in your rifles, it is bad ammo.

If it is bad ammo, IMI will do what any other ammo manufacturer will do, and that is blame you, your rifles, or something other than their product. Manufacturers can't afford to admit fault because of the liability inherent in saying "yep, we sold a whole bunch of dangerous ammo".

My curiosity would cause me to try and find out what is wrong with the ammo (if it is the IMI ammo), but once I learned the cause, I would probably just get rid of the ammo unless I had a whole bunch of it. If I had already bought a case of bad ammo, and could PROVE it was bad ammo, then I might try writing to the manufacturer, but the letter to the manufacturer would have to be very carefully worded so that I got a new batch of ammo without them having to admit that they sold a bad batch of ammo.