I'll also cast my vote for the 45/70 - of course I own one and load for it so perhaps I am biased. But, you have the capability of using anything from ~200 gn "button" bullets to nearly 500 gn solids, and everything in between, with cast, hollowpoint, softpoint, etc. available. The range of bullets available is large in this caliber. There are certainly many 44 caliber bullets available too but some number of the pistol bullets aren't appropriate for launching at ~2000 fps rifle velocities. Either will do plenty of damage to any deer or moose.