AR SBR Build What Caliber

[NativePride]

Ok What cal do you recommend for a AR Build with following conditions.

Condition 1 It Will be SBR Prefer around 10" Barrel And Suppressed

Condition 2 Will Be Suppressed when Legal to do so (Target Shooting and Legal hunting where suppressors are allowed.

Condition 3 Want to be able to use My New AR Milspec Receiver

Hunting mainly would be Hogs and where legal possibly deer.

I was Considering .300 Blackout or 6.8 spc as I think it would be hard to suppress a .223/5.56 SBR effectively.

I prefer enough knock down to get the job done.....

OK Hope I gave enough info now let me know your recommendations even if different caliber and why

 

[Gtscotty]

In a 10"-ish barrel length, I would go with 300 BLK... this one to be exact:

http://palmettostatearmory.com/index.php/catalog/product/view/id/15086/

For hunting, I'm more a fan of the 6.8, but in a barrel as short as 10", I'd probably opt for the 300 BLK. Also, personally I have a bunch of hunting rifles, so an SBR would primarily be for blasting and shooting subs suppressed. If you are leaning heavily towards this being your main hunting rifle, you should probably use supersonic rounds, and for that purpose the 6.8 might be a better choice.

 

[Sam1911]

If you wrote out a design spec sheet for a .300 Blackout, it would read just like that.

At this point, they're so mainstream and so tailored for that application that it's almost an open-and-shut question.

 

[Ranger Roberts]

3rd vote for 300 blackout. It fits all of the criteria you listed. Plus, even if you don't reload, you can buy 300 blk off the shelf at most sporting good stores now a days.

 

[Bullnettles]

4th for 300BLK. I have a 10.5" and suppressed it's one of the quietest guns I have. It's also accurate enough to hit at 80 yard and go through both sides the aluminum support of an old satellite dish mount clean at subsonic velocities. Perfect for hogs.

 

[HRnightmare]

For hunting I would say 300BLK. I however have a 10.5" 5.56 SBR with a Phantom 5.56 SS on it and it is unbelievably quiet. Shoots dirty as hell but it is much quieter than I expected.

I think the effectiveness of a 5.56 / .223 for hunting could be debated for hours, 300BLK would probably be more effective.

 

[Aaron Baker]

Since the obvious answer of .300 AAC has been suggested already, I'm going to go with the non-obvious answer: .458 SOCOM.

500 grain bullets are a hard-hitting subsonic load, and you can use a sufficiently beefy .45 suppressor on that platform as long as you stay subsonic.

Aaron

 

[NativePride]

At this point I think I am going .300 Blackout the 450 SOCOM look really nice as well but .300 can be bought locally pretty easy I may just have to dust the reloader off either way...

 

[Gtscotty]

http://www.radicalfirearms.com/category-s/1854.htm

Just thought I'd toss this up as a potential upper source. A melonite barrel and free float upper for $279... I don't see many reviews on Radical Firearms online, but the components look good.

 

[NativePride]

Gtscotty thanks for the link pricing looks pretty darn good....

 

[Charger442]

for hard hitting with good, cheap ammo and is quiet suppressed, i would SBR an AR in 45acp. But thats just me.

 

[Arizona_Mike]

300 BLK 10.5" BBL.

I did a lot of research and calculations before selecting this exact combo.

Mike

PS. Scope mount on backwards, yada yada yada . . .

 

[wally]

7.62x39 unless you like to reload or shoot $1.30+ per shot ammo.

You might have some issues with 7.63x39 AR magazines, but maybe discarding a few bad mags so you can use $0.24 per shot ammo vs. using $1.30+ per shot ammo is no serious burden.

OTOH if you enjoy reloading the .300 Blk is the way to go.

 

[Sam1911]

(And if you want to shoot subsonic...)

 

[Elkins45]

(And if you want to shoot subsonic...)

And if you would like to shoot cast bullets.

 

[TRX]

> .300 Blackout

I'll add my vote there.


> .458 SOCOM

A nice round, but ammo and brass availability is intermittent. I spent three months trying to find SOCOM brass before I gave up and went to .50 Beowulf instead. At the time, I could get Beowulf but not SOCOM.

 

[griff383]

I have a few 300blk SBRs and while I really enjoy them I might suggest the 6.8. I reload and make my own 300blk brass so that was an easy choice for me, but I have been looking at doing a 12.5" 6.8 SBR recently. From what I gather the 6.8 is a better all around hunting cartridge and the 12.5" barrel still maintains some great numbers but the 300 really shines with the components used and options of bullets/weights.

 

[jmorris]

I was Considering .300 Blackout or 6.8 spc as I think it would be hard to suppress a .223/5.56 SBR effectively.

I prefer enough knock down to get the job done.....

Why do you think it would be more difficult to suppress a rifle with a smaller diameter hole in the end of the suppressor?

Are you looking at loading subsonic rounds?

A 220 grain .30 cal bullet subsonic out of a 300blk has less energy than a 230 grain .452 bullet at the same speed. Not to mention a 45 acp bullet is designed for the speed it is running SS and .30 cal bullets work best over 2000 fps.

Once you set a speed limit, like the speed of sound, the only way you can gain energy is with mass. That leaves you with rounds like the 458 socom and 50 beo, they don't make a lot of 400-500+ grain bullets in small calibers.

 

[Bartholomew Roberts]

A 220 grain .30 cal bullet subsonic out of a 300blk has less energy than a 230 grain .452 bullet at the same speed.

Muzzle energy maybe; but depending on the ballistic coefficient of that .452 bullet, the .30 cal subsonic will likely catch up to it and pass it (in terms of energy) at some point prior to 300yds.

 

[jmorris]

Muzzle energy maybe; but depending on the ballistic coefficient of that .452 bullet, the .30 cal subsonic will likely catch up to it and pass it (in terms of energy) at some point prior to 300yds.

This is true, a Hornady 220 (.308) @ 1000 fps muzzle winds up having 351 ftlbs at 300 yds. That is 29 ftlbs (about 1/5 the power of a .22 LR) more than a Hornady 230 (.452) does.

The chances of a Hornady 220 expanding to a diameter larger than .452 at the speed it's running by the time it gets to 300 yds (848.2 fps) are about zero, unless it's hitting a steel plate.

Subsonic ammo is not the best choice for that range anyway. With a 50 yd zero, your looking at more than 11.5 feet of drop at 300, out of the above .308 load.

 

[jmorris]

To put things into prospective. A 405g sp moving at 1000 fps will have 146 ftlb more energy at 300 yds that the above 308 load would have at the muzzle and only drop 1.7" more than the 308 @ 300yds.

 

[NativePride]

Any recommendations for a complete 300 blackout upper in Flat Dark Earth? Having a hard time finding one.....

 

[Bartholomew Roberts]

Don't know anyone who makes one in FDE; but you can have it cerakoted the same color as Magpul's FDE.

 

[JeeperCreeper]

.22 LR..... jkjk
If you're going suppressed, I think you alread know the answer: 300 BLK

.... But if i were me, I'd do an AK PAP Pistol in 7.62x39 with a homebrew suppressor job on the cheap. But then of course my bright ideas always fail after I get them off paper

 

[wcoats]

Another vote for the 300 blk from me. I finished off getting a 10.5" 300 blk SBR and a suppressor a few months ago and it's exceeded my expectations. It's more accurate than I expected and you can do more with it using supersonic loads than I expected. Mine started out with just a red-dot, but now I have a 1-4X scope one it.


Also you can get ammo for about $0.6 a round, or a little less, without reloading. Here is an example from Ozark Ordinance for $0.56 a round. Their ammo seems to be loaded very consistently, with my rifle from a rest at 100 yards, with this ammo I can consistently get sub 1 1/2" groups measured outside to outside. So subtracting the .308" diameter of the bullet that's barely over 1 moa center to center.
http://www.ozarkordnance.com/300-AAC-Blackout-150gr-FMJ-Qty-250_p_15.html