The standard mauser is what we now call a long action.
The short belted mags like 264 Win Mag, 257 Weatherby, 7mm Remington, 300 Win mag, and 338 Win mag were all made to fit in the standard or long action like the large ring miliatry mausers. Or the same Over all length as 30-06
The magnum action was used for sporting rounds like 375 H&H or 416 Rigby.
Later the 300 H&H and the blown out version of it 300 Weatherby used the same action and then the other factory wild cats like 8mm Remington and 7mm STW.