Tough to really narrow down. My 1st instinct would be my 29-2 6 1/2" .44, as it shoots mags, specials and shot shells. And I usually hit what I aim at with it, large game or small. But I wouldn't exactly be overly handicapped with a S&W .460. That huge round, as well as .45 Colt. You could handle the big and the small. But then there's my 25-5 6" .45 Colt. Not too much recoil, and will cover about all the bases. Still, I reckon I'd likely stay with the big M 29, as it will do about all needs doing. (Hopefully, my reloading kit is included.) And MORE hopefully, this remains a "what if" kinda question...