10.5 AR pistol ammo

[felinesNfreedom]

Alright, forgive me if this has been posted. I searched but did not see anything, I might just suck at searching. I just finished my AR pistol build and was thinking about the best Personal defense rounds. Should I just stick with a 55-60 grain V-max or go heavier with soft/hollow point.... New to the AR group so I am not sure. I am tired of reading through other websites and just thought I would ask here. Thanks for the help.

[Clod Stomper]

I can't speak from personal experience, but I'd say that if you're using soft or hollow point bullets, either should be plenty effective.

[Oh Shoot]

My 10.5" gives over 2600 fps with even Russian steel stuff, (revised, see post below) with full powered 5.56 you're looking at 2750-2800 fps, plenty of velocity for the FMJ to do its thing.

 

But even with a 7.5" barrel, seems a soft point moving at 2300 or better would be plenty devastating.

 

- OS

Edited January 15, 2015 by Oh Shoot

[felinesNfreedom]

My 10.5" gives over 2600 fps with even Russian steel stuff, with full powered 5.56 you're looking at 2750-2800 fps, plenty of velocity for the FMJ to do its thing.

 

But even with a 7.5" barrel, seems a soft point moving at 2300 or better would be plenty devastating.

 

- OS

 

Thank you, everything I seem to read says that the round does not get up to speed so it can't fragment properly.

[Oh Shoot]

Thank you, everything I seem to read says that the round does not get up to speed so it can't fragment properly.

 

I revise my previous statement, looked up my file on results, was mistaken. FMJ needs 2600 fps I believe by general consensus to do it's thing. The few cheapo rounds I did chrono were borderline, and that's measured at muzzle too.  Any NATO spec loading will be much higher, though, and well in the effective velocity.

 

I found that diff between 16" and 10.5" barrel was about 300 fps.

 

---------------

AR-15 10.5" barreled pistol vs 16" rifle

3 shot average:

Monarch 55gr .223:
Rifle: 2929  Pistol: 2611

Wolf WPA 55gr 223:
Rifle: 2872  Pistol: 2546

Tula 55gr .223:
Rifle: 2843  Pistol: 2612

Federal Bulk 55gr .223:
Rifle: 2840  Pistol: 2536

---------------

Again, type of bullet matters a lot. If you're concerned about optimum "lethality", soft point or expanding don't depend on x velocity to work as designed in the way that the FMJ does.

 

- OS

Edited January 15, 2015 by Oh Shoot

[felinesNfreedom]

Thanks for the help OS. I think I will just roll with the V-Max bullets then. It is nice to know that the 5.56 loads should still fragment like it is supposed to.

[whitewolf001]

I think they issue Mk.262 rounds to guys running shorty's in the secret squirrel circles, which if I remember correctly is a 77gr SMK.

[Dolomite_supafly]

I would use the 77 grain stuff or BlackHills 69 grains stuff while I was working overseas. When we ran out of those we ran M855. But I would suspect any decent hunting round would work great for you.

[nightrunner]

I have read that the 70+gr is best out of a 10.5" or shorter barrel. Something like the hornady TAP

[felinesNfreedom]

I have read that the 70+gr is best out of a 10.5" or shorter barrel. Something like the hornady TAP

 

That's mostly what I read everywhere. Thanks for the info guys. DOLO I figured that if anyone could recommend something it would be you.