I have used BR-two's in 7mm rem mags with results, even in cold temps. But, that was with quite higher case fill of H1000 and Reloder 26, and Truthfully I prefer to use mag primers, they've not been detrimental to receiving constant velocities, so it will take away any fret https://devinwsato.ampedpages.com/the-ultimate-guide-to-remington-9-1-2-58735360