makes a detachable mag that with some machining will fit a BDL. They can be a bit tough to get up here in Canada...I have a 338Edge and love it! I wish I had more time to shoot it :( The one I have is heavy though... I've got a couple 300WM's that I'd like to convert one to the edge but with the goal of keeping it lighter.
I thought long and hard about getting a 300RUM but the 338's 300 SMK can't be beat although I'd like to try some of the heavy TSX's soon.
Don't hessitate, go "Edge"