THe .280 Remington is definetly not interchangeable with the 7mm Remington Magnum. Under no circumstances should you attempt this as it could indeed prove to be fatal to you as well as bystanders.

Both cartridges are loades with the same diameter bullets which are .284 inches in diameter. The difference is in the case size and design.

The .280 Remington is a 30-06 case necked down to accept the smaller .284" diameter bullets. Should you try to chamber a 280 remington cartridge into a 7mm Remington magnum rifle it will definetly fit. However the case diameter of the .280 is much smaller than that of the 7mm Rem mag and will instantly rupture sending the high pressure gasses in all directions including right back at you.

The 7mm Remington magnum is a cartridge based on the H&H case design. It has a belt at the bottom of the case and is much larger in diameter than the .280 Remington. Because of this the 7mm Remington Magnum will not fit into the chamber of the .280 Remington.


Also forget about the 7mm Express. The name was simply an attempt by Remington to promote some intrest in the .280 Rem and in 1979 they began calling it the 7mm Express. They have long since quit calling it the 7mm express and have long since quit stamping their cases with this name. You will not find any new manufactured ammo with the name 7mm Express. It is all called the .280 Remington.