Rifle vs Handgun AR

[Irish B]

So at close range your average fmj 5.56 round would cause more damage than your average jhp .45? It seems to me that even a soft point 5.56 would slice right through someone with very little expansion at say 1 yard away but I'm far from a balastics expert.

 

[jmr40]

That is what lots of folks used to think, but a lot of testing has shown that softpoint 5.56 actually penetrates no more in people, or common home building materials than handgun rounds, or buckshot. Less than some loadings. The handgun chamberings and shotguns used to be used more often because it was thought they would be safer. Testing has shown that a short barreled AR loaded with good softpoint ammo is just as unlikely to overpenetrate. For a variety of reasons this is why the shotgun is falling out of favor for LE and militaty use.

 

[Double Naught Spy]

So at close range your average fmj 5.56 round would cause more damage than your average jhp .45? It seems to me that even a soft point 5.56 would slice right through someone with very little expansion at say 1 yard away but I'm far from a balastics expert.

Why use a soft point?

With typical 55 grain ball ammo travelling at over 2700 fps (you should be getting well over 3000 even from a carbine at such close range), the round will quickly yaw in the body and tend to come apart, producing multiple wound channels while at the same time slowing considerably and hence tend not to overpenetrate or the parts that do manage to over penetrate do not pose a great danger down range. In short, you get good penetration in the body that produces a significant wound comprised of multiple wound channels and less danger down range from rounds that overpenetrate the body.

For example, see

Q. So, velocity is a critical component for the wound profile. How fast must the bullet be traveling when it hits its target in order to fragment reliably?

at http://razoreye.net/mirror/ammo-oracle/

Much of the heavier ball ammo will come apart at slightly slower velocities as well.

You will get more damage from your .223 round than from a .40 out of an M4 pattern AR15.

"I've never seen an indoor range that doesn't allow 556"

I've never seen an indoor range that DOES allow 5.56

I have seen both. There are a lot of ranges with peculiar restrictions. Some are necessary, some are simply rules based on the preferences of the range.

Just saying, in a few/some/many/most places indoor ranges are pistol caliber only.

Yep. Heck, I have even been to a couple outdoor ranges that would not allow rifle FMJ ammo, but never more than once have I been to any one of them.