The Gunsmith Thread

THParent said:
I had a customer totally fubar his AR-15 chambered for 5.56. He shot one round of .300 blackout through it.

One.

I had to cut the bottom off of the upper receiver to get the barrel off. He is lucky to be alive, so I told him to go and buy a lottery ticket.
I will come back to post photos. Stay tuned!
Click to expand...
It actually chambered?

Steve
 
Yeah. I didn't think it was possible for the firing pin to contact the primer with the back of the case sticking partially out of the chamber, but it did and it was fantastic in a SCLID* sort of way.

* Sudden Catastrophic Load-Induced Disassembly
 
THParent said:
Yeah. I didn't think it was possible for the firing pin to contact the primer with the back of the case sticking partially out of the chamber, but it did and it was fantastic in a SCLID* sort of way.

* Sudden Catastrophic Load-Induced Disassembly
Click to expand...
That would have been....interesting to observe from a distance.

I've seen some really dumb things done (even ended up treating an IPSC shooter at the station next to mine while waiting for the paramedics) but nothing like that.

Steve
USAFA ALO
USAFA '83
 
300 Blackout 01 reduced.jpg
The shooter is indeed alive and remains unscathed. If you look at the first photo, you will see (from left to right);
1. The .300 blackout case head (in 3 pieces), completely blown off the back of the cartridge case.
2. The rest of the case.
3. A steel bit (no idea where that came from)
4. A copper bit (I think it's the base of the copper jacket)
5. The copper jacket, now extruded to the size of the barrel (.224"), which lodged half-way down the barrel.

What you don't see is the lead bullet that the copper jacket was wrapped around. At the pressure that this explosion produced, the heat didn't need to be very high (lead typically melts at 621.5°F) to instantaneously turn the bullet into molten lead that literally "sprayed" out of the barrel. That's my best guess, anyway. I wasn't there when it happened.

So the forces pretty much were equal in each direction, which probably saved his life. Had he put something harder (like an armor-piecing round) in there, all the force would have been directed back into the breach. Considering what approximately 50% of that force did to the bolt and upper receiver (even the barrel had a bulge and split at its thickest point) had all that force gone rearward, it would have been a pipe bomb. More than likely he would have been DRT (dead right there).
 
Here's one I found that did the same thing, but with more fanfare:

1593229562450.png

And another:

1593229716335.png
 
I wish I had those guns in the last two photos. I just grabbed those off the Internet. :)
 
Dayum... may be a stupid question , but is the gun repairable ?
I am surprised that he even brought it in and 'fessed up to his stupidity.
(If damage isn't too readily visible, perhaps he can gt $100 at one of those gun buy back things....)
 
You must log in or register to reply here.
Back
Top