· Corps Commander NGV
Excellent advice! Thank you.I only own one rifle that uses a belted case, a 30-338 (which, other than neck diameter is the same case as your .264), single shot Mauser action gun built for 1,000 yard prone shooting decades ago so only have a little practical experience with them. From much that I have read, the belt was originally intended to prevent cartridges like the .300 H&H from having ignition issues because they did not have much of a shoulder to position the primer consistently against the bolt face. Belts then came to represent a symbol of a 'high power' cartridge so they were put on any round that the manufacturers wanted to 'hype', whether it really helped anything or not. The .264 has plenty of shoulder and doesn't 'need' a belt but, it got one anyway. If your .264 Mag seems to function fine with factory ammo you may not really have a rifle headspace issue but your sizing die could be short enough that you end up bumping the shoulder back and creating an ammo headspace issue. After checking your brass to insure that there isn't a really thin section right ahead of the belt (no point in tempting fate with more head separations) try turning your sizing die out a turn. Then work in slowly from there until the cases fit and you can close the bolt on the case with just a little effort.That will keep the shoulder where it fits your rifle and should prevent the problem.
That at least worked in my Wimbledon gun, I lost a number of cases to neck splits because I didn't know much about annealing 30 years ago but never had any head separations.