Well since my brther gave me his .308 converted spanish mauser that has problems feeding from the left side of the mag, how much of a pita will it be putting it back to its orginal caliber, 7x57?

Try a different mag spring. Seems dumb but they do wear out.

I bought a 03 Springfield a few years back the round wouldn't load from the one side, why I don't know. I changed the spring and floor plate out since i had one and it works fine now.


Converting back would be dumb you can buy a 7mm one cheaply.