My first "custom" rifle started out with a VZ-24 military action and a Midway 35 whelen barrel. A friend of a friend chambered it as a 35 whelen AI, it struggled to put three shots into 1 1/2" at 100 yds, with groups in the 4+" range typical. Needless to say, I wasn't happy. Through a sequence of events I came into a set of 350 Rigby dies and the loan of a 350 Rigby reamer. I sent the gun off to a real smith to have it re-chambered. I faced the action, re-chambered the barrel and cut a new crown. The gun subsequently struggle to shoot worse than 2" at 100 yds and it's best groups were 1/2". This from a sloppy miliatary action, two stage military trigger and a 2 1/2X scope.
Personally I wouldn't want to the added weight of a mauser action for a .270, but with a good barrel and good gunsmith, I would expect for all intents and purposes a 98 Mauser to be as accurate as a Remington 700 for a hunting rifle.
