IMO if your load's velocity exceed those listed in Hornady's book (who lists 7x57 loads for modern action)you might be playing with fire. Of course you rifle could have a loose bore too.
3000 fps w/a 140 is getting into 7x61 territory that is a lot bigger case built for a lot stronger rifle (Schultz & Larsen) than a lot of ex miliary Mauser 98s.
