Remington is the only one that makes .350 Rem Mag cases. I bought some brass several years ago, that had been made from 7MM Rem Mag cases. Have never gotten them out of the bag. When Remington discontinued making the .350 ammo back in the mid 90s I bought all the ammo the gun shops had in my area. So I have lots of cases to work with, probably enough to last me the rest of my life. I don't shoot either of my .350s a lot, too much recoil to feel comfortable. I only use them for bears over bait, they work good for that. The Remington 600 is a beautiful little gun. Love to look at it, and let others admire it's good looks. Hate shooting it, but it is devastating on Black Bears at 10 to 20 yards.