Originally Posted by gamedog
RWS is supposed to be some of the best.
RWS is the best I'm aware of. Lapua stopped manufacturing 300 Win Mag brass between 1 and 2 years ago. Lapua is very good also if you can find some. Both the RWS and Lapua will cost significantly more than Winchester. Within the past month someone advertised some RWS 300 Win Mag brass on this Forum. If you do a search you should be able to find it.
RWS brass will have a strong case head, meaning they will handle higher pressure before the primer pocket swells and loosens up compared to Winchester, Federal, Remington, or Norma.