I have a 110 in .270 with the factory sporter barrel. I'm looking to upgrade to an aftermarket barrel, but need to know what shank size is....small, med., or large? Its a center feed mag model with accutrigger.

Also, looking for a sporter aftermarket barrel for around $250 or so that will shoot one good group. I know with a skinny barrel in .270, you only get a few shots before that bad boy gets smoking hot. Any suggestions welcome.