RE: 7mm Ultra Mag
Correct, they are totally different cartridges. There is only one factory load for the 7mm RUM, 140 grain Core Lokt Ultra from Remington. It's a good load though.
If you look around you can still find factory loads from the past few years.
The 7mm RUM is a handloaders round. I would advise loading your own, or finding someone you trust to load you some. I've had great luck with the Hornady Interbond in it.
Erik
Rusty Axe Camp