I have the chance to trade a benelli pump shotgun for a Left-Handed Remington 700 BDL 300 RUM sporter. Good deal?? If I do get to go through with the trade, I think I am going to build a long range set-up off of this action. I am trying to decide what I caliber I want to change to since I don't really want a .300 RUM with a sporter weight barrel or any weight barrel. It just costs to much to shoot and the cases have a short life. Which long range calibers can you build on this action that would be the most economical (as far as ammo/reloading) and performance wise? What common calibers have the same size bolt face as the 300 RUM? I was thinking maybe a 300 win mag or 7mm Mag. I have a friend with a lathe and milling machine that I am going to use for the build. He has started doing a little custom work on the side and from what I can tell he does a good job (especially fluting and threading). All I will have to do is supply the parts, and he will do the rest for free just to show his work off.