AR blowup

[DLT]

If I blew up one rifle I wouldn’t chance the second

 

[gdbleb]

The 4the Edition of the Sierra Reloading Manual shows a load range of 22.9 to 25.9 for H335 for their 55 gain bullets in the 223 rem. However, this is for bolt rifles.

Wow! Data sure does change. I have the 5th Edition of Sierra's manual.
55 gr bullet page - bolt action - H335 - 23.0 gr - 27.5 gr
55 gr bullet page - AR-15 - H335 - 23.6 gr - 25.7 gr

 

[divingin]

A) Damn near impossible to double charge a 223/5.56 round using normal powder. Not enough case capacity.

B) "Blew up" can be all kinds of things. Normally an AR will blow out the magazine, blow off the dust cover, crack the upper. Extreme cases will distort and/or bulge/crack the lower. The barrel extension may be split open, as may the barrel at the chamber. A squib plus fired round can do all of that plus bulge the barrel further up the tube. Bolt face be split open, and the bolt carrier can be bent or broken.

C) Post catastrophe forensics are tough, but helped a lot by viewing the damage to the rifle, viewing the cartridge case remains, and trying to figure out what went wrong to cause the damage.

Bottom line: Pics would help. Nobody is going to be able to come up with a rock-solid theory from "My rifle blew up. What happened?"

A few questions to clarify things:

Did you work up your loads from a lower powder charge?

Was your scale calibrated?

Your charges that you broke down and measured have a 5% error. Were you throwing directly into the cartridge or measuring each charge? Assuming the Hodgdon max of 25.3 and the amount of variance in your cartridges, your charge error could well have been over on a few.

How old was your powder? Was it from a consumer package, or was it bulk military pulldown powder?

I've personally seen 2 AR's blow up. One was from loading pistol powder instead of rifle powder. That one was particularly spectacular. The other was from firing a .300 Blackout round in a 5.56 AR. Both can be attributed to the shooter (he also did the reloading in the first example.) One M1A; due to an overcharge (not a double - just ignoring warning signs of high pressure until the rifle failed.) A couple of bolt guns; probably poor loading; can't say I remember what caused those. Lots of pistols/revolvers, mostly due to squibs, with a few double charges thrown in.

 

[RED DIRT]

Nothing figured out yet....?????
Pics or a video would be good instead of all this guessing.

 

[Coyotefurharvester]

I have ran 3 different 55 gr bullets thru 3 different AR's, running 25.0 H335. Range brass, zero issues and actually pretty accurate out of all three. 1. 556 chamber. 2 223 Wyde. Cases all eject between 3-4 o'clock. I have been running a light crimp(Lee) as a final step. I check rounds using a Lyman ammo checker, if it doesn't drop fit, it doesn't go into a magazine.

 

[dellet]

Two different AR 15’s blown up with the same load.

Let’s blame the rifle.

 

[SecondsCount]

One other thing to consider.

I'm not going to pin this on mixed brass but if everything lined up, a little bit higher charge and a little smaller case capacity will increase pressure. Probably not enough to blow things up but something to consider.

 

[writerman]

What do you mean when you say we tested the powder? How did you test it? Is the powder commercially packaged H335 or milsurp pulldown. Did you check the bullet dia with a mic? Bad brass? Unsupported case head in the chamber? Maybe an issue with the rifles not the ammo?

Have you ever had this happen, and what happened?

 

[writerman]

Some photos of the "blown up" rifles might be helpful in trying to diagnose what the problem was.

The bolt carrier split, the extractor blew out along with the retaining pin, the steel magazine blew apart, the upper cracked, the lower had stress marks on it. I can send pics. in a bit.

 

[RabbitSlayer]

If there were no pressure signs at the target charge weight, it seems it would have to be waaaaay over charged to cause the gun to blow up. I mean yeah, you might have something bad happen like a stuck case, but to have a catastrophic kaboom seems unlikely...

 

[writerman]

Uh……my Hornady book shows MAX at 23.2.

Lyman goes up to 27.

 

[writerman]

Throwing, or weighing every charge? I'm going to assume throwing, as that's quite a range of charge weights if your target was 23.5 grains.

Case length greater than 1.760" could be the problem.

Mixed brass: Internal volumes can vary quite a bit. What headstamp of brass blew up in the rifles?

Pictures would be very helpful.

Would a case length cause that though? I read lots of threads of guys who don't even trim. They shoot up to 1.800 with no problems. For 250 rounds I weight the first three charges and throw the rest, because usually H335 is close enough to spec, and since the charge weight is 23.5 and Lyman goes up to 27 grains, I figure one grain off isn't goind to cause this. I have to go back and measure BOTH chambers now. The first rifle I rebuilt and immediately went out and successfully shot 20 rounds of H335 at 22 grains. Have you ever had this happen?

 

[writerman]

Like he said ... what do you mean by "blown up"?

The bolt carrier split, the extractor blew out along with the retaining pin, the steel magazine blew apart, the upper cracked, the lower had stress marks on it. I can send pics. in a bit.

 

[writerman]

What do you mean when you say we tested the powder? How did you test it? Is the powder commercially packaged H335 or milsurp pulldown. Did you check the bullet dia with a mic? Bad brass? Unsupported case head in the chamber? Maybe an issue with the rifles not the ammo?

Commercially packaged in the bottle right from Midway.

 

[writerman]

All things considered, I would send the powder back to the manufacture. Or the garbage can.

Out Of Battery Detonation AR

I had an out of battery detonation, brought the destroyed .223 AR to one of the best gunsmiths in town, and he just shook his head and said he thought it might have been 'something about the round the gun didn't like.' I reloaded 100 rounds, same everything, no variation in that box at all. 50...

forum.accurateshooter.com

Unless there is more or better information.

What information do you need, and have you ever had this happen?

 

[mike mccormick]

Ok, I guess I will be the one. Your reloading practices are terrible. Trim to length is 1.75, yet you allow cases up to 1.765 ( the ones you measured). You have a charge variance of 1.6 grains, again, of those you measured. You are using mixed brass, which can vary greatly in capacity. All of this on a small capacity cartridge to boot. Not to mention, all of this and you crank out 250 rounds without even a test fire to check charge weight. Then you post up here, already defensive, looking for reasons why not one, buy two guns" blew up", that do not point the finger at yourself. Go back to the basics of reloading. Do a lot of reading. You nay save yourself a lot of pain.

 

[writerman]

Have you measured your chamber? If the barrels from the two blown up rifles are still around.
The reason I ask is if the chamber were right at 1.760, the cases that are 1.765 would be crimped by the throat and cause higher pressure.
Brownells sells a really cheap chamber measure.
If you have a borescope you can insert a case into the chamber and insert the borescope from the muzzle.

I do use a Wilsom chamber guage on ALL of my reloading brass. I use it if it passes inspection, and then slips into the guage easily, without having to push it in. All else goes into the trash.

 

[writerman]

Ok, I guess I will be the one. Your reloading practices are terrible. Trim to length is 1.75, yet you allow cases up to 1.765 ( the ones you measured). You have a charge variance of 1.6 grains, again, of those you measured. You are using mixed brass, which can vary greatly in capacity. All of this on a small capacity cartridge to boot. Not to mention, all of this and you crank out 250 rounds without even a test fire to check charge weight. Then you post up here, already defensive, looking for reasons why not one, buy two guns" blew up", that do not point the finger at yourself. Go back to the basics of reloading. Do a lot of reading. You nay save yourself a lot of pain.

Hey, I am willing to learn. I just wanted facts and personal experiences. According to all the data I have read, none of those variables should have caused this. You can bet, I will be more meticulous in further reloading, and I am going to trim under spec, like the new brass you get. No more mixed brass, I'm going to start with new. Defensive because I wanted information or comments like yours, not someone's opinion of 'double charges' which they were hardly that. They were all within book specs. I always start two grains under max. and usually stay there. Lyman goes up to 27 so I don't see the problem. Do you think it might have been a long case that crimped in the chamber, and still locked up? I have read numerous reloaders who load up to 1.800 and they have had no problems. I don't get it, but I won't do that. How do you 'test fire' a charge weight safely?

 

[karrarararararar]

Did the kabooms happen on the first rounds fired?

 

[writerman]

You asked for personal experiences. The only firearm I personally witnessed "blow up", meaning the firearm damaged, was a 1911 45 ACP. This was due to a barrel obstruction, a round fire into the pistol that had a bullet lodged in the barrel.

Firearms are supposedly proof tested before leaving the factory with ammo well over SAMMI pressure specs. So, something caused a tremendous pressure surge.

The 4the Edition of the Sierra Reloading Manual shows a load range of 22.9 to 25.9 for H335 for their 55 gain bullets in the 223 rem. However, this is for bolt rifles.

Military cases are known to be thicker thus requiring some reduction in powder charge.

I have personally experienced pressure surges with ball powder (namely H335 and H380) in extreme field temperatures of 90+ degrees, ammo exposed to direct sunlight in the field. These surges exhibited themselves in hard bolt lift, extractor engraving on the rim of the case, and extreme flattening of primers. In all cases the powder charges where below published maximum for that bullet. However, the rifle did not "blow up".

What where the environmental conditions and how many rounds of sustained fired were there when the firearm "blew up"?

Most of the catastrophic failures that I have read about were due to either incorrect powder mistakenly used, a double charge (pistols), incorrect ammo, or a barrel obstruction.

Trying to find the answer on the internet especially without a picture is a shot in the dark at best. If it was me, I would take the damaged firearm to an experienced gunsmith, along with ammo plus all information you have on the firearm and have it inspected by a professional.

I took the firearms to two professionals. One shook his head and said 'it will happen if you reload enough.' The other took apart all the remaining rounds and also shook his head, saying that given the varying specs, none of them would or should have caused this to happen. I don't care where the fault it, I just want to as definitively know as much as I can, so I don't do this again. Thanks. I will post pics.