SBR thoughts, what caliber?

[brianakell]

Thinking of the SBR thing. However, what ammo would be best suited?
options being .223, 7.62x39, and 5.45x45
.223 is pretty common, though the others arent rare
5.45 seems to be more effective at the tumble thing sooner, and cheapest
x39 real similar in cost to .223, and with the tapered case, aides in extraction, and running in dirty conditions.

There's plenty of argument on which is best. However specifically in the SBR world, what has the more practical use? And how short of a barrel could you go before drastically dropping off velocity, accuracy with each? For arguments sake, say all mags are same cost, and have no feeding issues, Id like to stick to ammo vs barrel, and typical surplus/cheap ammo, not reloads.

[DFBrews]

krink in 5.45 they are sexy.

[TriggerHappy]

This is my baby, she runs like a dream. 10.5"

[Great-Kazoo]

Which has the widest spectrum of bullets and component availability? Answer that and you have your next caliber picked out.
I like the 223 / 5.56 round as parts availability / support in an AR config is hands down more readily available than either com-bloc caliber. Sure 5.45 is cheap, sooner or later you will run low. 7.62x39? components , just not the choice's 5.56 offers. How often do you see 7.36x39 Brass at the range......

[lead_magnet]

7.62x39, you can buy alot of it cheap, still very lethal out of a small barrel. Mags are cheap, reliable and easy to come by. Several AK pistols that you can easily convert into a SBR. Plus with the AK platform you can fold the stock, you don't have that option with AR.

Ammo: Brown Bear 123gr
16" AK: 2300fps
Draco: 2000fps (11.5" barrel)
Mini Draco: 1900fps (approx 7-8" barrel)

I can fit my Draco SBR in my 511 select cary pack, with a hydration resivior, extra mags, a full size handgun with light and mags and go out shopping and not turn any heads. (Before I get flamed, I don't actuaily do this, but I do have the option, Macy's can get downright dangerous on black friday)

Here is some random guy from BARFCOM on Velocity out of a SBR AR:
"Had a chance to chronograph some ammo out of my 6.5" barreled AR.


62gr Am Eagle - 1861 fps
55gr UMC - 1939 fps
45gr Rem Varmint - 2302 fps"

Piss on all of that.

[Great-Kazoo]

7.62x39, you can buy alot of it cheap, still very lethal out of a small barrel. Mags are cheap, reliable and easy to come by. Several AK pistols that you can easily convert into a SBR. Plus with the AK platform you can fold the stock, you don't have that option with AR.

Ammo: Brown Bear 123gr
16" AK: 2300fps
Draco: 2000fps (11.5" barrel)
Mini Draco: 1900fps (approx 7-8" barrel)

I can fit my Draco SBR in my 511 select cary pack, with a hydration resivior, extra mags, a full size handgun with light and mags and go out shopping and not turn any heads. (Before I get flamed, I don't actuaily do this, but I do have the option, Macy's can get downright dangerous on black friday)

Here is some random guy from BARFCOM on Velocity out of a SBR AR:
"Had a chance to chronograph some ammo out of my 6.5" barreled AR.


62gr Am Eagle - 1861 fps
55gr UMC - 1939 fps
45gr Rem Varmint - 2302 fps"

Piss on all of that.

Doesn't matter what caliber you're shooting. Hitting the target is what counts.
One who practices with a 22 is superior to one who doesn't with a 45.

[275RLTW]

You can run ALL of those with the same lower...just buy different uppers.

[jreifsch80]

i would say 7.62x39 would be the best for an sbr between those 3 choices. plus it's probably the easiest to suppress the most and you can load some thumper subsonic loadings. think of it this way, anything the 300 blackout can do the 7.62x39 can do too and sometimes better (a guy i know has an ak that does dime sized groups at 100 yards with his custom barrel and handloads)

[TriggerHappy]

You can run ALL of those with the same lower...just buy different uppers.

+1, that is if you stick with an AR chassis.

[brianakell]

If I'm understanding this right, the x39 is dropping ~15% at 8", and the .223 is dropping more like 30%? 5.45 should be real similar to .223 for velocity. If this is true, then the x39 would be better suited to sbr, as its not dropping near as much at the other 2 calibers.

Any other ideas welcome!

7.62x39, you can buy alot of it cheap, still very lethal out of a small barrel. Mags are cheap, reliable and easy to come by. Several AK pistols that you can easily convert into a SBR. Plus with the AK platform you can fold the stock, you don't have that option with AR.

Ammo: Brown Bear 123gr
16" AK: 2300fps
Draco: 2000fps (11.5" barrel)
Mini Draco: 1900fps (approx 7-8" barrel)

I can fit my Draco SBR in my 511 select cary pack, with a hydration resivior, extra mags, a full size handgun with light and mags and go out shopping and not turn any heads. (Before I get flamed, I don't actuaily do this, but I do have the option, Macy's can get downright dangerous on black friday)

Here is some random guy from BARFCOM on Velocity out of a SBR AR:
"Had a chance to chronograph some ammo out of my 6.5" barreled AR.


62gr Am Eagle - 1861 fps
55gr UMC - 1939 fps
45gr Rem Varmint - 2302 fps"

Piss on all of that.