Not much choice for 6mm Rem brass. Rem, Win, and Horny is all i can find. Bought a box of 50 Hornys at Sportsmans the other day and 3 of them had splits. 2 of them at the neck/shoulder junction and 1 at the case mouth. Would like to buy higher quality brass and form it but unsure weather to start with 7x57 or 257 roberts ? Anyone have any thoughts on making 6mm rem from these cases ??