Re: 300 rem Ultra Mag
I shot a Rem 700 LSS in 300 RUM for about 2 years. I put 1200 rounds through it in that time period..I saw great accuracy and performance from this caliber and rifle. The rifle was basically stock except trigger work and glass bedded/free floated. I tried various bullets from 150-220g but settle on 200g AB @3200fps, or the 210g VLD @3000fps. I used the 200g AB load to take a few elk, the farthest being 525 yards. I shot a few 4" 3 shot groups at 800 yards w/the rifle and its preferred loads on a good day..I could regularly hit a 15" steel plate at 1150 with the 210g VLD's..
All in all, I think its an awesome caliber, but a little more power then what you need most of the time. Thats why I downsized back down to a 7 RM. You just dont need that much power unless your shooting over 600 yards all the time..Any 7 RM or 300 Win can get you to 1K with the right bullets, so burning 30g more powder is just kinda waste, IMO. If your shooting farther then 1K and want to kill elk at 1200-1300 yards the RUM's are probly your cup of tea...
I was using a Leupold MK4, 4.5-14x50 LR/T w/regular duplex reticle. It was a great scope, but I wanted more magnification and fine duplex so I traded it for a VX3 6.5-20x50 LR/T w/fine duplex. A lot of peolpe are Nightforce fans though and they are hard to beat for $1300 price range..