What is up with this 5.56 case?

[KurtM]

Nope, Jevapa is right, it won't fit a 300 B.O. what meant to type was 350 legend, but I 'blacked out"

 

[JEVapa]

Would it have fired if out of battery? I was fighting a case sizing die once that left it just out of battery and it would fire. Just a click.

Out of battery simply means the bolt doesn’t go into battery (fully lock). So if the bolt doesn’t lock, nothing’s holding the cartridge.

That said, ref the 300BLK, as long as one can pull the trigger and drop the hammer, and causes the firing pin (inertia) to hit the primer, it’ll go. It would depend on how much gets shoved into the chamber I would think but I’ve never seen it or heard of it. I don’t think it’ll go. Apparently a 300BLK will go in a 556 catastrophically.

I do think it’s from a 556 gun because the case mouth is still 556-ish diameter. It would be opened up to 30-ish cal in a BLK. He probably had a dry gun or some crap in the extension. The biggest culprit we always saw was leftover cleaning products like chunks of those little felt star chamber cleaners or pieces of patch and q tips.

 

[sherrick13]

Well, it is NOT .222 Mag






And the case mouths. It does seem to still be .223ish

 

[sherrick13]

Here is another tibit of interesting information.

As you would expect the fired .223 will swallow a .223 bullet. Drops right in.

The weird fireformed case will not take the .223 bullet. It is like a resized .223 case ready to be loaded.

 

[sherrick13]

Checkout the primer.

LOL, I don't think I've ever seen a convex fired primer.

 

[sherrick13]

Stress marks?




I'm thinking now an OOB fire, but I don't see how the case didn't rupture.

 

[1Mudman]

Looks like they were case forming another Ackley but either not enough powder or may they had it stuffed with cotton and corn meal and just didnt get it formed?

 

[2busy]

Looks like it is lake city brass. Looks like the primer crimp is missing. That's all I can contribute.