Robert Ruark has content on youtube. I had read some about him and Harry Selby. So I gave one his old films a view. He said he carried a shotgun with buckshot for back up because the cats are too fast to use sights. I had never considered that, being completely lacking in experience.

I'm sure a scoped centerfire rifle of sufficient caliber is without rival for shot placement on unsuspecting cats at distance. Same as other game. I've also read that current thinking favors rifles for backup.

I have a Rem 700 Mnt gun 30-06 I had used for elk before switching to a muzzle loader. Im sure it would work fine. I'd likely want a better quality scope of fixed low magnification.