Originally Posted by chlinstructor
Originally Posted by elkhunternm
A 6mm Rem is a 7x57 necked down and so a .22-6mm is a.22x57.

Here is my "22x57" or aka .22-6mm.


I could be wrong, but I always thought the 6mm was based on the old 6 Lee Navy Cartridge ?


chlin: Nope that's the 220 Swift.

The 6mm Remington is based off he 7x57(or 257 Roberts).



The 280 Remington is overbore.

The 7 Rem Mag is over bore.