My father has built a 6.5x55 as well as an 8mm-06 off of one. If you reload and want a .338 cal, the 338 Sherman (based off the .270 or .280 case) may be a good option, 250's up to 2850 fps-ish with good brass, and would likely only a rebarrel to achieve.
The 338 Norma mag will take a new barrel, opening up the bolt face and modifying the extractor claw, opening up the feed rails, or likely converting to a center feed, which would include fitting a new mag box, which may need machining to the reciever, or you may need to add an extended mag box to run the 300 bergers at proper length (just under 3.700" in a CIP chamber). That is if your gunsmith thinks that the action is strong enough to convert it to a .585" bolt face. Not saying it's a bad idea, if it is strong enough that would be a cool rig. With 250's you would get roughly 2900+, and 300's you would get 2650 or better (this is with a 26" barrel). In a 28" .338 norma with Peterson brass I am running the 300's at 2815 fps.