I have some of abt. every brand of primes here now. I might also and that I load for 3 different .17 cal. round, 5 different .22 cal. rounds and several most larger rounds. For case that take small and are .223 or larger I always start load development with Rem. 7 1/2 primers. Most of the time they are the best choice for accuracy, but not always. If your groups are 1 in. or larger I doubt that you need to spend the extra monet for BR primers and your accuracy will probibly be the same with mag. primers, or posibily even standard primers.