I know, it's a stupid question but I see so much about it, and yes I did search first and didn't find exactly what I was looking for. But I want to know, what's so great about it and is it worth the extra $30 to have Kreiger 5R a 7mm barrel I'm thinking about picking up? Does anyone here have 2 really similiar rifles one with and one without the 5R and if so how do they compare accuracy wise? Does 5R change pressures (probably the most stupid of all, but I have read that rifling configuration can change chamber pressures as the bullet is in the first 2-3" of a barrel's rifling)