Over my reloading life I have done a lot with reduced loads and they will shoot.

For example, 39 to 41 grains of H4227 (and no filler) in 375 H&Hs with 220 grain Hornady flat point. Does about 2100 f/s and in a friends 375 it shoot 1 inch 10 shot groups. What about 85 grains of IMR4064 and 500 grain Hornady in the 460 Wby for just over 2000 f/s and full accuracy and no fillers.

HOWEVER, I think there are two ingredients that are required for reduced loading to be the success you want it to be.

1) You have to like playing about with loads.
2) You need to be able to do your reloading while shooting so as to experiment.

One other point. Contrary to popular opinion smaller bores on a given case tend to be easier to work with as ignition is easier. In other words a 300 Ultra would be easier to play with than a 375 Ultra.

Mike

Kazoo,one of my best friend hunts almost exclusively (all big game) with his 300 RUM, he also almost always uses min loads and lighter bullets. His rig is a Hill Country custom job, so maybe that helps, but we shoot a lot at the range and that thing flat drills the eyes out with a lot of different loads. I know it ain't all Chris, cause I've shot it too, and equally good groups. Chris hasn't had to pull the trigger but once on any game animal he has shot. I will say that with full loads it is a beast on recoil. My 300 WSM's (mostly SAKO's) shoot about as well, but at full max it ain't the monster that the RUM is of course.
Good luck and good hunting--D.

I own three of them, but if you aren't going to load it up fast, just get a .300 WSM. Unless you practice at very long ranges (the only distance the RUM really makes a diff), the .300 WSM is plenty. I can hit just as well out to 600 yards with my .300 SAUM as a .300 RUM. The only advantage at lesser ranges is wind, but it doesn't sound like you are going to go out and practice at 5-600 yards plus in windy conditions anyway.

Just my two cents...

Trying to decide on a .30 cal and have a question on the 300 ultra mag. Are there any disadvantages, reduced accuracy, when downloading the UM to '06 or 300 win mag velocities? I have no need to shoot the UM at highest velocities for a majority of my hunting but would like to have the surplus for the occasion that I will use it out west or in AK. The two other contenders are the 300 WSM and the 300 win mag.... So many choices so little time to become one with all....