Re: 300-338 rum?
You will have to rechamber, the 338 rum is around .100" shorter in the case body than 300 ultra case. Be careful when you do this and clearly mark the barrel 338-300 ultra not 338 ultra. This is why I call the 338-300 ultra the 338 EDGE, I don't want any confusion about what can be fired in it. If you fired a 338 ultra in a 338-300 chamber it will be a really bad day. Once you have covered your bases I believe that the 338-300 is the best bang for the buck in the LRH market right now.