With a thinner brass wall design, the results may lead to an over-stretching (i.e. 308 Winchester is specified for a ‘hotter’ powder load than that of the 7.62, firing it in a chamber with the added headspace will stretch the brass much more than the lower powder load 7.62. The published difference in this headspace between the two cartridge cases is approximately six-thousandths of an inch – small, yet, significant.īearing in mind that the. This is to help insure fast, easy feeding and ejection through rapid-fire sequences (i.e. Typically, military rifles are made with slightly longer chambers (longer headspace). 308 Winchester cartridge case and the 7.62 NATO case is the chambers they are specifically designed for. Too high of pressure may result in a primer leak and other pressure problems.Ĭhamber Design: Perhaps the real difference between the. All things being the same, the thicker case (smaller capacity) will generate a higher pressure. In turn, reloaders should consult their Reloader’s Guide and adjust their powder loads according to the specific calibers of the rifles they will be fired from. 308 case cartridge, it follows that the powder capacity of the 7.62 is lower than the. Additionally, the case cartridges must withstand the rigors associated with automatic weapons.īrass Thickness: Because the 7.62 case cartridge has thicker walls, yet has the same external dimension of the.

across multiple platforms (the thicker brass is better able to stretch and accommodate these chamber variations). This design feature is to accommodate NATO specifications, which include varying chambers specs. In general, military brass is thicker than commercial brass. Barrel chamber length for the different cartridges.The difference between the two, beyond the outside dimensions, is basically two-fold: In fact, the 7.62 was developed using the general design of the. 308 Winchester cartridge case and the 7.62 NATO (7.62 x 51 mm) are the same thing. From an external dimension standpoint, the.

Calibre library stretch cover