I have a 300 RUM in a Rem 700 with a Leo VX-III 4.5-15x50 and my Buddy bought the same thing in the 7mm RUM. I broke both of these guns in (because i have very nice facilities for such things). I have the following to say about these guns. Both shoot MOA groups. The 300 has slightly more noticeable recoil but very manageable. The 7 has more factory load choices, but how many do you really need for these calibers. I shoot the Rem 180 Sciroccos, flat shooting and great performance on game. If you reload there are endless possibilities. Having shot both and seeing game shot by both I would not trade my 300 for the 7 for even money. I think you have a wider range of knockdown power with the 300 and unbelievable range. If your going to go after bigger game you would be silly to give up that power for no logical reason. Saying that, the 7 is a great weapon. By the way the Buddy with the 7 is planning on getting a 300 short RUM.