just seeing whether a single shot rifle would be more accurate than a lever gun or a ruger bolt gun.
Too many variables to answer a question like that.
I have owned and shot Contenders for almost thirty years in a number of chamberings in factory and custom barrels. I shot two Encores last year with Bullberry barrels that were as accurate as any factory bolt rifle I've ever shot.
I currently have two factory Contender carbines that will shoot right along with bolt rifles.
If I were looking at a single shot .357 or .44 magnum I wouldn't hesitate to buy a Contender or Encore. For maximum accuracy potential, I would buy either a Bullberry or MGM barrel for it.
An 18" barrel carbine in either .357 or .44 magnum would be just the ticket for deer hunting under 150 yards.
Ed