#1). .270 WCF was the original hot rod. Working pressure at 55K CUP from the start. That was "hot, hot, hot" for the 1926 introduction. Or 1925 some say. Great gun. Great history. But not for Rider Rollling Blocks, etc.
#2). De Haas has a standard I subscribe to. If the action was made before 1930 or 1920 if you wish to be generous, keep to the older, lower pressured standards. .30/'06 -- 45K CUP. .250 Savage. Etc. [A Mr. Titus, pre Mr. Ackley in his books, was equalling the .270 WCF with the .300 Savage necked to .270 with the pre WW II powders available!] If you can find a well made Mauser made after 1930, "go for it." Probably the most numbers made of any bolt rifle. Proofed in the 80K CUP range. Should handle reasonable .270 loads forever. Should. Luck.