Out Of Battery Detonation AR

[Kracken McGraw]

Note to self. Stop being a hoarding miser and sell that old mixed stamp brass that worked fine last time

to the scrap yard.

Could always blame stink bugs or the ladybug look alikes. Dang things love my loading area.
Glad all re ok.

But do you think new Lapua would of held for that load. I’m giving it a No.

 

[dellet]

197 replies. Which one is correct?

“Yes”
“it was not out of battery”

 

[wildcatter]

if the brass is soft from a bad anneal that ejector swage would happen on a normal pressure load.

i take it that no one here is familiar with forging of metal. I have been working in the metal forging business for over 20 years. When any metalis soft it will flow. Especially if the op'er does not know the history of the brass.

I seen it here from a local shooter. He scrounged brass at a local gun range. Every year they burn off the grass. Guess where he got the brass right after they burned the grass. Two weeks later he blows his gun up exactly like this. The brass was annealed dead soft from the fire.

Case heads blow out like this all the time. It just happens. ALL of you guys are assuming that the barrel, bolt, brass, load were all in spec. And if they were this would not happen.

I take it a lot of the guys here are not that familiar with how the AR system works and it shows. I have now given you 3 things that could all leade up to what happened. I don't think he messed up the loading one bit. That 23.5 load is safe for any 556 rifle. 25.3 is max for a 223 cartridge using a 55gr bullet. A 556 can go even higher.

Normal pressure might blitz a balloonhead brass case, but it sure don't destroy the entire gun!

 

[wright brothers]

Kraken I do not know but the 50-1 odds thing grabs attention.
And I probably won't scrap em but have lower milage brass on hand.
Still blame the insects lol.

 

[243winxb]

Primer Output and Initial Projectile Motion for 5.56- and 7.62-mm Ammunition.​

https://apps.dtic.mil/sti/citations/ADA622138

Open the PDF. See- "5. Conclusions"

I had primers fire, with no bullet movement in a 22-250 cartridge. The H450 (discontinued) powder started burning & just stopped. CCI mag primer, years ago.

 

[jelenko]

Primer Output and Initial Projectile Motion for 5.56- and 7.62-mm Ammunition.​

https://apps.dtic.mil/sti/citations/ADA622138

Open the PDF. See- "5. Conclusions"

I had primers fire, with no bullet movement in a 22-250 cartridge.

Interesting. They seem to be clearly saying that primer alone with move the bullet into the lands
As I've already said, it's never happened in any of my 223 rounds that didn't have powder.
Though, I've never used 41's - just 7 1/2's, 450's and Fed Match AR's.

 

[DShortt]

Interesting. They seem to be clearly saying that primer alone with move the bullet into the lands
As I've already said, it's never happened in any of my 223 rounds that didn't have powder.
Though, I've never used 41's - just 7 1/2's, 450's and Fed Match AR's.

I screwed up in the past and skipped the powder charge. Immediately put the rifle away until I could throughly investigate the cause. Never had a bullet move enough to notice.

I probably use too much neck tension.

 

[Old Navy]

7400s would blow or jam with Remmington factory ammo. If you want to compare use a gun that wasn't flawed to begin with Like the Browning auto rifle

Never had a problem back in the day with any factory ammo in my 742 or 7400. And if built my reloads to duplicate factory 150s they worked fine. Just couldn't shoot a good group with them.

 

[VA_XTC_Shooter]

Interesting. They seem to be clearly saying that primer alone with move the bullet into the lands
As I've already said, it's never happened in any of my 223 rounds that didn't have powder.
Though, I've never used 41's - just 7 1/2's, 450's and Fed Match AR's.

I have had empty cartridges lodge the bullet in the lands with just primer (Rem 7.5 and Fed 205). Bullet in lands prevented the second round from chambering when cycling by hand (XTC rapid fire). Not much force from cleaning rod to pop out the bullet and fire the alibi.

Perhaps neck tension? I use a 0.221 mandrel for my brass.

 

[jelenko]

I have had empty cartridges lodge the bullet in the lands with just primer (Rem 7.5 and Fed 205). Bullet in lands prevented the second round from chambering when cycling by hand (XTC rapid fire). Not much force from cleaning rod to pop out the bullet and fire the alibi.

Perhaps neck tension? I use a 0.221 mandrel for my brass.

I run the same neck tension - using Forster FL and RCBS X dies. And, no crimp.

At the same time, I always stop and check the round before proceeding.
For matches, I weigh all my rapid fire rounds to check for missing powder.

 

[drop_point]

"""ruined an extractor in a 700 by grabbing the wrong box of ammo. It was a perfectly safe load in my ARs, but too hot for my 700."" Ok if you say so .

I do say so. So did the gunsmith. I wish it weren't true...but it trashed the extractor.

 

[Uncle Bruce]

I run the same neck tension - using Forster FL and RCBS X dies. And, no crimp.

At the same time, I always stop and check the round before proceeding.
For matches, I weigh all my rapid fire rounds to check for missing powder.

I load on a single stage press. Before I move to seating bullets I take the loading tray and actually look into each case to make sure that the powder fill is there and all look the same. EVERY TIME

 

[Webster]

“Yes”
“it was not out of battery”

A battery powered rifle!

 

[Winchester 71]

DILLON MACHINE PLUS A MOMENTARY DISTRACTION EQUALS KERBOOM......HAPPENS MORE THEN PEOPLE ADMIT TO...................................................

 

[neckturner]

loaded with H335 23.5 grains, OAL 2.245.

Quickload shows this with 55gr fmj as 88.5% fill and modest pressure with the default case internal capacity.

Let's see what happens if we put more in by mistake, or through a powder bridge in the drop tube (which subsequently lets go, creating an overcharge):
100% fill == 62351psi, right at max
105% fill (which you might not notice, it would 'crunch' but the bullet would seat) == 74725psi, which is likely "kaboom"

This is an overpressure round, as others have said, based on extrusion into the ejector. The different brass could be a coincidence, or you got doubly unlucky and overcharged a case with less internal capacity.

 

[ebb]

The op posted this March 31, the info that comes up after his name says he joined April 2 and last visited April 3. Guess he didn't like hearing it was one of his loads that was the problem. I hope he figures it out so he doesn't hurt himself.

 

[David Milisock]

There is no way you'll ever know for sure what happened, trash the firearm and start again.

 

[ebb]

David, from the pictures he already trashed the firearm.

 

[David Milisock]

David, from the pictures he already trashed the firearm.

I meant do not reuse any of the parts!

 

[dsinfour]

First thing who built the AR 15 ? First thing I would do get a whole bowl carrier changed that out and check the gas system. If not, it’s unsafe to shoot. Take it out put it in the garden make it make a tomato steak out of it. He