I have a reamer for the 338 edge and I punched out my 338 win mag, like Gene stated complete powder burns are a bit touchy but it does work ok with lighter bullets and lil faster powders. My 338 win mag was good to 400 or so and now I feel good about taking shots out past 600-800 yrds. Here in Pennsylvania its hard to find long distance shots on whitetails. So basically I ended up with a nice medium to long range deer setup and can still load heavy for black bear hunting also...