I found a ruger stainless 7 mm Remington short mag This gun has to be rare but its useless without ammo and brass .They even had it in a custom stock .I knew there were too many calibers many ha e disappeared quickly !
I did not know that Ruger made a 7mm SAUM either, but I do like to buy guns that are different. I have a Ruger in 300 WSM and a Rem 700 in 7mm SAUM. I bought about 300 rounds of brass for the 7mm SAUM so I enjoy shooting it. As long as you have brass it is good. Of course you can use 300 SAUM brass so I don't think that you will run out of ammo.