5744 and 300 Blackout
I've had good luck with the CMMG upper using 18.5 grains 5744, Sierra 2121 125g HP flat base, and CCI small pistol primers. I load to 2.225 in LOA. I worked up to this load carefully and never went beyond 18.5 grains when I got 1.5 MOA.
I bought quanity 5744 during...