Well I can't resist any longer. Personally have never used the 7mmRM but for around 30+ yrs. hunted with 2 brothers who did.
One bought a box of Remington factory ammo (150 gr.) every year, shot 10-15 rnds./yr.
The other guy bought whatever was cheapest that year and shot about as much.
Between the 2 of them there is likely 2-3 life times of factory ammo sitting!
They were 2 of the deadliest "meat shooters" I have ever known!!
I used a Schultz & Larsen 7x61S&H for a few years. It worked.
I have an Interarms 7mmRM I may get around to trying out this fall or not.
The 275 Rigby has always been more than ample for me!

66 in May

"The more I am around people the better I like my dog." Mark Twain