Considering a new AR caliber

[greywolf2112]

OK, I'm thinking of selling my 9mm AR upper (8" barrel) and going another route.

My criteria: Accurate, reliable, can be reloaded (ammo) relatively cheaply, would be nice if I could use standard mags but have no problem buying proprietary if I need to (if I don't already have mags that will do the trick), uses a regular AR-15 lower.

I want it to be a rifle with good short and medium range capabilities (especially in terms of energy delivered on target - I'd like it to be good for hunting medium sized game and hogs, with good defense/anti-personnel uses if TSHTF).

I'd like to go with a 14.5" - 16" barrel max.


Here is what I already have:

.300 BLK in 16"
.300-221 in 8" (will probably convert to .300 BLK)
5.56 in 16"
5.56 in 14.5"
LaRue OBR 18" (heavy sucker)
6.5 Grendel 20" (somewhat heavy sucker)

So, would I be best served with just another, much lighter weight 16" or 14.5" Grendel? Or is there something else out there that might be in the cards?

[WC 2-3]

I was considering putting together a 6mm/223 upper. Easily done, just not sure if it's enough benefit. I only intended mine to be short/medium range coyote gun.

[OTO27]

6.8 will do everything you are asking for.

[motorwerks]

6.8 will do everything you are asking for.

I opened this ready to say .308. But he speaks the truth!

[Jake'sDad]

That .300 BLK is quite interesting. If the rumors are true that there will be affordable ammunition for it, I'll be very tempted to get an upper built.

[DocGKR]

12" 6.8 mm w/Battlecomp BABC

[LMTRocks]

I'd say to go with the 6.5 G but only if you're going to scope it. A red dot on a 6.5G is like putting a drag racer on a basketball court....so much power yet the ability to reach out and smash the target is limited with the optic. Reloading components will run you to around $0.35-$0.40/round. And you're right---it is a little heavy. My 20" tips the scales at 12lbs with a JP/VTac rail, 4-16x50 Vortex optics mil/dot scope and 1pc mount, and a SOPMOD stock.

[Nevermiss]

12" 6.8 mm w/Battlecomp BABC

We have a winner! Unless of course you want to run it suppressed. Unfortunately, Battle Comp has no intention of making any changes to he BABC to mount a suppressor.

[The_Hammer_Man]

+1 to 6.8 SPC!

If you're not going to run it suppressed ,and have no plans to do so, I'd consider doing this....

get a quality SS 1:11 or 1:12 14.5" and have it cut to 13.7 and rethreaded.

Then add/pin-weld a pws FSC30. It's JUST long enough to bring the barrel up to the required 16.1".

If on the other hand you already have an SBR lower then completely disregard the previous and get :

DD 12.5" in 6.8.

The 6mmx45 is a great round.. just wish ammunition was more readily available.

[greywolf2112]

I'd say to go with the 6.5 G but only if you're going to scope it. A red dot on a 6.5G is like putting a drag racer on a basketball court....so much power yet the ability to reach out and smash the target is limited with the optic. Reloading components will run you to around $0.35-$0.40/round. And you're right---it is a little heavy. My 20" tips the scales at 12lbs with a JP/VTac rail, 4-16x50 Vortex optics mil/dot scope and 1pc mount, and a SOPMOD stock.

I was thinking of a Vortex Viper PST 1-4x scope when they come out. I already have the brass/bullets/dies for 6.5 - I was thinking of 110 or 100 grain bullets at some high velocities for the close-in stuff.