RE: 270 WSM ????
Generally if you are using an extremely light/fast bullet in a barrel rifled tighter to stabilize larger heavier bullets, it will reduce the life of the barrel. If you do not shoot 100 rounds a day I wouldn't worry about it. If you shoot factory loads through a stock factory WSM rifle I would not worry about it. Careful what you read on the internet, watch the source of the information, there is A LOT of bunk out there. I have a Kimber 270 WSM and have no problems what so ever.