I posted this on Snipers Hide to get a little more insight, but I figured I'd get more useful experience from the AR crowd over here.
I recently picked up a 18" BCM SS410 complete upper to compete in the DMR matches held within my region. I had VERY good luck with the Rainier Arms 18" Match Barrel in the past, so I figured the BCM SS410 Match Barrels would yield similar results. I tested the following types of ammo:
Freedom Munitions .223 69gr HPBT
Freedom Munitions 5.56 77gr HPBT
Federal Gold Medal Match .223 69gr (Sierra Match King bullets)
Fiocchi .223 69gr (Sierra Match King bullets)
Fiocchi .223 77gr (Sierra Match King bullets)
IMI 5.56 69gr (Sierra Match King bullets)
IMI 5.56 77gr (Sierra Match King bullets)
I shot two 5 round groups back to back (minus time to prep/reload magazine) on the Larue .5" Grid Targets you see below @ 100yds. The one with three different variants was shot back to back but with the different types of ammo. It was an indoor range, well lit, and using a Vortex Viper PST 2.5-10x32.
I guess I expected more out of this setup and am curious if this is normal? If it is, then so be it. However I was wondering if these groups look sporadic or perhaps indicative of an underlying issue? If so I'll reach out to BCM to take a look at it and give me their verdict.
Below is what I was able to get out of the Rainier Arms Match Barrel with 69gr and 77gr Federal Gold Medal Match as well as PPU 75gr and what my expectations were based on.
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