.312 bullets can be used for?

[Gatorade]

Ok the Mauser and the .303 British are in the family library of firearms. However I don't plan on shooting either of those so I will probably pull the bullets and powder and wait till I have 7.62x54R brass. Then I will see about dies. I was really bummed when I found out they were .312 and not .308. If they were .308 I could use them for 300 Blackout but .004 more would not be good.