17 rem savage

Keep your .270 Winchester, the .270 WSM is shorter and a larger in base diameter. These new 'short" magnums have less case surface area to grip the chamber walls and generate much more bolt thrust. These new cases are harder on the bolt and receiver and some rifles have had damage done by the increased bolt thrust.

Bottom line, the Ackley improved cartridges with even more surface area generate less bolt thrust, and the "new" short magnums have less surface area and generate even more bolt thrust.

http://en.wikipedia.org/wiki/Bolt_thrust

http://www.eabco.com/WSM01.htm

http://gunsmithtalk.wordpress.com/20...-thrust-tests/