Originally Posted by idaho elk hunter
The 7 mm RUM is really the better choice of the Hyper Velocity 7mm caliber. The REAL problem is it came out to soon. When Berger, or if Berger releases its 195gr 7mm projectile and when RL33 comes more readily avail along with Vita Vouri H570 I assure you the ballistic differences will be readily apparent. The RUM should be chambered in a Very hard barrel like a Lothar Walter and be stressed relieved with a minimum length of 28 inches up to 34 inches. If a rifle was built but a knowledgeable smith it would out perform all other 7mm cartridges. My fear once this technology comes apparent to the rest of the world the rifles chambered for the Rum will have the wrong twist rate and wrong throating to work in harmony with what I described above. I have built 2 of these rifles and can say not much will run with them. Only the BIG 338s will best them. Check out the projected claim of the 195gr Berger 7mm and run some number of this at 3200 fps. And that load is lazer flat and hard hitting at 1000+ yds. Compare this to the 30-378 or any other and tell me what you think!
The 195 berger may make a difference; rl33 will not. The 7 stw is already capable of using 50 bmg type powders like rl50 and I 5010. The extra powder capacity is a moot point. 86 grains rl50 in my 7stw will break 3100 fps with a 171 in a 24" barrel. Kick the bbl length up to 28" and I'd be closer to 3250-3300 fps with a 171.
As far as the "hard barrel" if I were to chamber a 7stw in the same barrel make as your 7rum I'd still see twice the barrel life at around 100 fps velocity drop (if that). Apples and apples please.
I do like the 7rum and may own another eventually but it is really an over design with little benefit over the stw other than it gets rid of the belt. The drop in bore life with the 7rum is a non issue for some, but I don't like the idea of playing with a new barrel every couple of years.