Nightcrawler
Member
Okay, I see a certain contradiction in the supposed performance of .223/5.56mm FMJ ammunition.
All the AR makers these days say that .223 FMJ will fragment and penetrate less than a pistol round, except in body armor, in which it apparently doesn't fragment.
They say fragmentation happens in multiple layers of obstruction. This apparently does not apply to steel; I've shot .223 FMJ ammo through an old steel pot helmet, a 55 gallon drum, etc. It went in on the near side and out on the far side without slowing down much.
A .45ACP pistol round and a .357 Magnum round (from a 16" barrel) did not exit out the far side of the helmet, in my own little tests. .223 and 7.62x39mm both went clean through.
Now, I'm willing to bet that drywall makes for poorer armor than steel. I've also seen AR advocates claim that SS109 rounds will penetrate a kevlar helmet at 1100m, and that they'll out-penetrate .308 FMJ.
And this is all with FMJ ammo.
Here's what I don't understand. In my OWN OBSERVATIONS, .223 did NOT fragment all of the time. In fact, it stands to reason that hardball ammunition, not designed to fragment, would NOT RELIABLY FRAGMENT.
Nevertheless, I'm assuming fragmentation is the key. Otherwise, it makes no sense. How else could a rifle round moving at 3100 feet per second penetrate less than a pistol round chugging along at 900fps?
So what's the REAL story? I've read the reports of the FBI tests on Olympic's page. On the other hand, the tests done by High Road/TFL members I've read do not seem to substantiate the claims of the FBI.
I'm really confused on this.
All the AR makers these days say that .223 FMJ will fragment and penetrate less than a pistol round, except in body armor, in which it apparently doesn't fragment.
They say fragmentation happens in multiple layers of obstruction. This apparently does not apply to steel; I've shot .223 FMJ ammo through an old steel pot helmet, a 55 gallon drum, etc. It went in on the near side and out on the far side without slowing down much.
A .45ACP pistol round and a .357 Magnum round (from a 16" barrel) did not exit out the far side of the helmet, in my own little tests. .223 and 7.62x39mm both went clean through.
Now, I'm willing to bet that drywall makes for poorer armor than steel. I've also seen AR advocates claim that SS109 rounds will penetrate a kevlar helmet at 1100m, and that they'll out-penetrate .308 FMJ.
And this is all with FMJ ammo.
Here's what I don't understand. In my OWN OBSERVATIONS, .223 did NOT fragment all of the time. In fact, it stands to reason that hardball ammunition, not designed to fragment, would NOT RELIABLY FRAGMENT.
Nevertheless, I'm assuming fragmentation is the key. Otherwise, it makes no sense. How else could a rifle round moving at 3100 feet per second penetrate less than a pistol round chugging along at 900fps?
So what's the REAL story? I've read the reports of the FBI tests on Olympic's page. On the other hand, the tests done by High Road/TFL members I've read do not seem to substantiate the claims of the FBI.
I'm really confused on this.