Only thing I ever hit with 7 mag and ran off into senders. Have read there are one step below water buffaloes on toughness. I stepped up to 338 Lapua 300 gr burgers. We usually Shootin 300 plus yards
I use a drill chuck to hold brass. Drill on drill press. Then chuck tap in drill press and turn by hand. Ream brass to slip fit Bullet. I use a sized brass.