Haven't tried RL50, but have used H50BMG, VV20N29 & SW50BMG, AT V4, AMP every reload (only get 4-5 firing on Barrett brass before neck split), weighed primers to .002gr. Best is cheep Shooters World BMG with an ES of 64 with 36 rounds for SWULR comp. Pushing 500gn A-tips 2900-2960. They come...