Re: .300 RUM seems to give ejector marks very easily ?
Just yestarday I put about 35 rnds through 270x300RUM, doing some load developement. Most loads started with 95 to 97gr and worked up to between 103 and 109gr, every other shot left some kind of ejector mark on it. But when you start to see the mark getting real shiny. Beware, the brass is starting to flow and pressure is getting high. If I remember correctly cartridge brass starts to flow @73k psi. That is if my memmory serves me correctly. Just the same SAAMI standards are set @63 or 65K psi as max. For most newer cartridges.