Monster 12” - First Rounds Fired

[SBRSarge]

Got the Monster 12” built. BCM upper, Coda Evolution hand guard, Detroit Gun Works lower w/ Geissele SD-E (flat bow) and STR stock, SiCo Omega hanging on the end of the barrel, Leupold 1.5-4 VX-R scope, Odin tunable gas block open about one turn. 

The barrel looks great. It mounted into my BCM with very little heat needed where most other barrels in BCMs need to be heated a bit. I tried it on three BCMs and all were the same. I could have whapped it with a mallet to seat it, but did the heat anyway. The threads were a bit rough but seem to be smoothing out with a few runs on-off with a thread protector and the SiCo can.

At the range, I fired a few shots to get on target (it was already there pretty much, thank you laser bore sighter!), then I shot two five shot groups at 100yds. Flawless cycling, and probably can be tuned down a bit more, but my hex wrench was too short. (Yeah, I know, I opened the door for ‘tool is too short’ jokes.)
 
Group Sizes:
Black 1.5”. 

ELD-M  .95”.


Velocities; 

Black 2395 w/ S.D. 37.0 (ouch!)

ELD-M 2396 w S.D. 12.7


All in all, I am happy. I might swap a better scope onto it and shoot for some serious groups. My 20” Odin is averaging .75moa with a Trijicon 4-16x.

[BluntForceTrauma]

So far, so good! Thanks for the report.

Decent velocities; wonder where they'll end up when it's broken in?

The shorties can be a bit squirrelly to shoot. If I remember correctly, LRRPF52 on 65Grendel.com recommends a strangle-hold, death-grip on SBRs for best accuracy.

[SBRSarge]

SBR ARs are like owning a Belgium Malinois, they require a firm hand!

At least with the Omega on the end it gives it some mass out there to counter any muzzle flip. Next trip out I’ll work it a bit more with the Black and expect to see moa or better. In my 18” Odin, the Black seems to shoot as well as the ELD-M.

[SBRSarge]

I looked back in my chrono logs. As a point of reference, the Barnes 110 gr BlackTip in a 12” barrel 300blk gets about 2250 fps or so.

The 6arc has similar bullet weight, better B.C., ~150fps more velocity. What’s not to love?

Now we just need some good subsonic loads and supersonic all copper loads.