AR-15 BS Thread

Holy Cow
How many rounds had been through it and was he working it hard when THAT happened?

 

Uhhhhh....


Anyway, just picked up 5 billet matched sets from CMT.

 

wouldn't that have caused a bolt/barrel malfunction not a upper malfunction?

 

Yea it doesnt matter what he was shooting the structure of the upper was comprmised to do that, i mean hell they make them out of polymer too. I know this much i wont ever buy a stag. M&P FTW!!!!!!

 

Look at the very bottom of the bolt carrier. It is split open too and there are pieces of the barrel still covered up.

They have been making AR parts rather fast like here lately, this one might just be a metal issue, not heat treated, heat treated too much to become brittle, etc. Hopefully we hear what caused that to happen.

Check out this technical bulletin from Federal, especially the last paragraph.

http://le.atk.com/downloads/technical_bulletins/223VS556.pdf

 

He may have had a squib. Right? There's a few post on cgn and arf about uppers looking like that from squibs. Shitty ammo probably...

 

The only mark that matters is the barrel stamp, shouldnt matter what is marked on the lower. But yea the bolt is split like a log, didnt see that before on my phone. I reload a lot of LC .556 brass that i shoot in my bolt rifle and i typically stay off max by atleast 5%. Basically i load for my AR-15 and use the same ammo in my bolt action.

 

http://www.ar15.com/forums/t_3_118/622954_Would_an_AR_15_Work_on_the_Moon.html

 

http://www.straightdope.com/columns/read/2282/would-a-gun-work-in-space

 

is it safe to assume you meant to say "shooting a 556 out of a 223 upper"?

 

No. He meant shooting 223 out of a 556 upper.

 

So then that wasn't the problem, because doing that is completely fine

 

Was he shooting reloads?

 

Guys, I wasn't trying to say that is what he did, I just know what he ended up with looks like what happens sometimes when you shoot a 5.56mm round in a barrel chambered for .223. As I said parts are being made fast nowadays and if you follow that link to Federal it plainly says they have found .223 chambered barrels on guns with receivers marked 5.56mm. I was just trying to get the point across to not mix the ammo unless your barrel truly has a 5.56mm chamber. Same thing with 7.62x51mm compared to .308, not the same animal.

 

The problem with the .308 is the reverse of the .223. You can fire NATO ammo in a .308 chambered rifle, but if the rifle is indicated as a NATO chamber, commercial .308 ammo should be a NOGO.

 

I thought it was that way, any idea why they weakened the load on the nato to 308?

 

It's not the load. The NATO rounds in x51 have a thicker brass case. The chamber walls are thinner in old NATO chambered rifles....

 

ahhh, that makes sense

 

What rev said. The difference between .223 and 5.56 is inner dimensions not out dimensions. The case wall is thicker in 5.56 so the pressure of an exact load in a 5.56 and 223 will have a higher pressure in the 5.56. Other differences that won't affect the chamber is 5.56 usually has crimped primers and harder primer cups to decrease chance of slam fire due to the floating firing pin.

Reloaders keep your head stamps sorted correctly and use proper reloading techniques and you're fine.

As for that rifle it can be any number of things that caused it. It may not even be a stag upper just because the lower is marked stag. How many of you guys buy random lowers to mount uppers on? A squib is very feasible since everyone is scrounging ammo wherever they can. Also there a million crappy BCGs out there people are jumping all over for $65-80 complete. All of the pressure of the rifle is contained in the locked up bolt, BCG and barrel extension. The upper receiver is not containing the pressure it's soft aluminum that can't contain 55k psi of pressure. So a crappy aftermarket carrier or bolt could have done this. After the scare started slowing down I had plenty of no name companies that aren't around trying to sell me this crap to sell. I refused and chose to stick with well known products.

 

...and now thanks to Brett, I have Young carriers coming out my ears