Has anyone had this problem? 300 Win Mag. The case is splitting right above the belt. I am using a 168 Berger VLD, with 74 grains of H 4350. The Brass is on its second Load. The load is not too hot, but could be a little cooler. I shot some factory ammo through the rifle, and it is showing a faint ring where the reloads split. The rifle is a Thompson Center Pro Hunter.