AR blowup

[Coyotefurharvester]

I think the op has figured out the problem, cases that were long for the chamber, jamming the unfired round tight. Greatly increasing the pressure in an individual round when fired. Why all my AR rounds drop fit an ammo checker.

 

[DGP4]

Something just doesn't add up. The catastrophic failure you describe would not happen from a slightly overcharged case or a slightly long case. I have loaded 1000s of .223 with H335. Then again, going to maximum load on unknown brass would not be advisable in any scenario. Also, cases that were that far out of spec as to length might tell you that they were subjected to unusual stress before you ever laid hands on them. The simple maxim to start at the starting load and work up your load is the best advice.

 

[SeabeeKen]

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 agree but add the over length case when crimped could chamber but not release bullet. Some reloading practices here need to be improved. Lucky nobody was killed or injured. Progressive press?

 

[mac86951]

I think I have figured it out. It was a series of mistakes I will never make again. I built two AR's for a close friend, one of them being a .223. Well, he went out and bought 1000 rounds of once fired military brass. First problem, the cases are slightly less in volume, so produce more pressure. Then even though he was an experienced reloader, he had no case guage for .223 and did not measure his cases. These were the first two AR's he owned. He was getting on in years and passed four weeks or so ago. That's when I bought a lot of 1000 primed .223 cases from his estate, and promptly loaded them. I DID NOT CHECK CASE LENGTH. Second mistake. Some were nearly 1.780. This is why I was puzzled when I found cartridges overlength in my stuff, when I always measure. But I incorrectly assumed that he had measured them, because he had fifty years of reloading experience. I figured incorrectly that they had been measured, since I always measure and trim before I prime. My bad. Maybe he bought them pre-primed, I don't know, I never will. I should have measured them. That whole bad bag was all stuff from his estate. The combination of military brass and overlength I believe is what did it. The cases crimped when fired causing what was a mimic of a squibb in the chamber, blowing out the back of the brass and destroying the rifles. Had I trimmed the cases, given the loads even with the variances, they would have been fine. Never, ever, trust reloading from anyone else, period. That was the lesson. I got it. They were all either 25 grains of H335 or under, and my AR manual specifically lists 26 grains as max. for an AR. I am going back through all 1000 rounds and measuring each one with my Wilson Case guage, and pulling any one of them 1760 over. The powder wasn't the problem so I'm saving it and using it to reload all the correct length cases now. What a huge job. But I like my face. Thanks for all the replies.

Sorry to hear! Thanks for the update.

 

[jds holler]

Something just doesn't add up. The catastrophic failure you describe would not happen from a slightly overcharged case or a slightly long case. I have loaded 1000s of .223 with H335. Then again, going to maximum load on unknown brass would not be advisable in any scenario. Also, cases that were that far out of spec as to length might tell you that they were subjected to unusual stress before you ever laid hands on them. The simple maxim to start at the starting load and work up your load is the best advice.

If the case is too long for the chamber, --- well that is very bad. No one should disregard that as a no no. jd

 

[wedgy]

I think I have figured it out. It was a series of mistakes I will never make again. Thanks for all the replies.

I really appreciate the humbleness and patience you displayed in this thread. They usually degrade in to name calling, insults, and nothing is learned or resolved.
A big thank you sir !

 

[Rocketvapor]

Borescope each of my barrels.

 

[JB10]

I know everyone says dont mix brass and i understand why, but i do it all the time for 2 of my ARs. I also use h335 but stay off max. Im just looking for 1moa or better with them at 100 yards. I also test them before i load a bunch just to make sure all looks good. They are coyote rifles. Now i have a real nice wilson combat ar and that has matching brass. Sounds like the too long brass probably caused ur issue

 

[writerman]

I'm gonna say that I'm also using H335 in my new AR, and as per a suggestion from a member here, I went down from 25 gr. to 24,(55 gr. Max) getting a measured velocity of 2950+/_ a few fps. Accuracy is better (one inch-ish at 100) than with the hotter load. (as he said it might be) -- AND I always like going for greater margin of error, especially when I might want to use a batch of skanky old pick-up brass of bastard linage. jd

I find the lower velocities to be more accurate as well. That's why I was going for 23.5 instead of the Lyman limit of 26. I was still way under Lyman max. It was cartridge length I believe. Went through 1500 rounds this afternoon, pulled all over 1.760 and trimmed them. Not making that mistake again. Had to pull about fifty. Yeow.

 

[writerman]

I know everyone says dont mix brass and i understand why, but i do it all the time for 2 of my ARs. I also use h335 but stay off max. Im just looking for 1moa or better with them at 100 yards. I also test them before i load a bunch just to make sure all looks good. They are coyote rifles. Now i have a real nice wilson combat ar and that has matching brass. Sounds like the too long brass probably caused ur issue

Too long brass was the only obvious problem. Other than the blown up rifles of course. I was thankful I didn't get hurt.

 

[writerman]

Looks like you might have a good handle on it. You screwed up, you trusted someone else. Didn’t listen to some others who tried to help

As for penance, go back through both threads and count the number of times you stated “in spec” or “measures right”.

You also might consider moving to a different town. If both the best gunsmith and the best reloader both missed a pretty rookie mistake, none of the shooting ranges in the area are safe
Only you can keep yourself safe. Good you stuck with it

Oh, I learned many valuable reloading tidbits this mishap. I am also paying a LOT more attention to each and every detail, period. I mistakenly believed all was well, when I could have caught it had I been more vigilant. Again, I trusted somebody else's work, and he was getting on in years and missing things. My bad. I am a better reloader out of this for certain. Now I am no longer so confident, and more cautious.

 

[writerman]

Sorry to hear! Thanks for the update.

You are welcome. I am relieved, now that I know what happened. I went through ALL my recent reloads from his estate and ended up having to pull and trim about fifty. Fifty! Wowser. Going to be more careful in advance now. Thanks.

 

[writerman]

I agree but add the over length case when crimped could chamber but not release bullet. Some reloading practices here need to be improved. Lucky nobody was killed or injured. Progressive press?

No, single stage. The fault was in trusting that primed brass had been trimmed. It hadn't. I always trim before priming, so assumed my friend did as well. My mistake. He wasn't familiar with AR's. Just starting out.

 

[writerman]

I really appreciate the humbleness and patience you displayed in this thread. They usually degrade in to name calling, insults, and nothing is learned or resolved.
A big thank you sir !

Ha, well, thank you. It's pretty humbling when you make a mistake and then cannot figure it out. All I cared about was not doing it again. I assumed my friend had trimmed before priming like I always do, but he didn't know to do that with the once fired lot he bought. God bless him, he's gone now, and apparently his legacy lives on. LOL!

 

[writerman]

Here you go:
https://www.brownells.com/reloading...s/sinclair-chamber-length-gage/?sku=749000811

Thanks! But the description says 'should not be used in semi-automatic rifles.' Oh, well.

 

[writerman]

I really don’t need any more data or info. Between the two threads I think it’s clearly a load problem. The question is what.

When you look at various load data, 23 grains and a 55 grain bullet can be a starting load, or a max load depending on the actual bullet and seated depth. That says that following guide is very important and substituting components and measurements is critical.

With the numbers you provided, the first load the bullet was seated at 2,45” with 23.5 grains and blew up a rifle. The second load was 23.5-25 grains seated at 2.05” with brass so long that potentially could pinch in the chamber due to length and base to shoulder measurement. This means the second load was higher pressure than the first load. Or maybe. Just the same variables with more information. Again the rifle blew up.

So now you have the same components, assembled in a way to create more pressure, and another blown up rifle. Something about doing the same thing over and over expecting different results come to mind.

The powder charge should be safe, at least to the point of expect maybe a popped primer over pressure symptom. Not catastrophic failure pressure.

That gives me enough reason to question the powder. Your loads are a problem, but I would not expect the near fatal results you’ve had. I think it’s the wrong powder or it’s gone bad. Either way not worth the effort of loading anything with it again.
Disregard the above if this is a fresh container and not what you used to last time.

I’m sure Hodgdon would love to have that powder back. If they sold mis labels powder, they want it off the streets. If they can prove the powder was contaminated , they can avoid liability. This is how recalls start.

If you look at my posts in your other thread, I posted a photo of what roughly 125-130,000 psi does to an AR upper. Yes, I have experience blowing one up.

I’m not sure H335 can develop that kind of pressure with 25 grains without another problem or two. But a pinched bullet can act just like a blocked barrel.

Again I think the powder may be suspect, but your loading process is without doubt guilty.

If you read my recent thread comment, the best guess was that it was pinched brass from a too long case. It acted like a squibb but not as drastic, because the bullet did leave the barrel. It's amazing how much pressure can build up so fast. Made a mistake assuming my friend had trimmed before priming them. Will never trust anything but my own work from now on. Period.

 

[dellet]

Ha, well, thank you. It's pretty humbling when you make a mistake and then cannot figure it out. All I cared about was not doing it again. I assumed my friend had trimmed before priming like I always do, but he didn't know to do that with the once fired lot he bought. God bless him, he's gone now, and apparently his legacy lives on. LOL!

You’ll remember him fondly every time you pull the trigger, and flinch

It’s a hard lesson, the one I posted in your other thread was a double charge. It was a distraction. Wife let me know dinner was ready. I simply turned my head, replied, turned back around and charged the case again.

After picking up the pieces, weighed all the remaining cartridges. Found one about 8.5 grains light. Pulled the bullet, no powder.

Sometimes you can’t even trust yourself.

Honestly, you’re lucky he had some others that were long. Without those, you might never have figured it out. Gotta look at the bright side.

 

[Webster]

I think I have figured it out. It was a series of mistakes I will never make again. I built two AR's for a close friend, one of them being a .223. Well, he went out and bought 1000 rounds of once fired military brass. First problem, the cases are slightly less in volume, so produce more pressure. Then even though he was an experienced reloader, he had no case guage for .223 and did not measure his cases. These were the first two AR's he owned. He was getting on in years and passed four weeks or so ago. That's when I bought a lot of 1000 primed .223 cases from his estate, and promptly loaded them. I DID NOT CHECK CASE LENGTH. Second mistake. Some were nearly 1.780. This is why I was puzzled when I found cartridges overlength in my stuff, when I always measure. But I incorrectly assumed that he had measured them, because he had fifty years of reloading experience. I figured incorrectly that they had been measured, since I always measure and trim before I prime. My bad. Maybe he bought them pre-primed, I don't know, I never will. I should have measured them. That whole bad bag was all stuff from his estate. The combination of military brass and overlength I believe is what did it. The cases crimped when fired causing what was a mimic of a squibb in the chamber, blowing out the back of the brass and destroying the rifles. Had I trimmed the cases, given the loads even with the variances, they would have been fine. Never, ever, trust reloading from anyone else, period. That was the lesson. I got it. They were all either 25 grains of H335 or under, and my AR manual specifically lists 26 grains as max. for an AR. I am going back through all 1000 rounds and measuring each one with my Wilson Case guage, and pulling any one of them 1760 over. The powder wasn't the problem so I'm saving it and using it to reload all the correct length cases now. What a huge job. But I like my face. Thanks for all the replies.

Why would you load 1000 cases at a time If you didn't like the resulrs would you pull 1000 bullets and dump the powder. The chambers shoud be long enough to accomodate any cartridge neck length.

 

[jelenko]

Thanks! But the description says 'should not be used in semi-automatic rifles.' Oh, well.

So it does.
I've been using one for awhile now.
I would love it if someone knew why they shouldn't be used in semi autos.

 

[Rocketvapor]

Soft steel will deform if the bolt isn't run forward EASY.