Travis,
Probably my Ruger Blackhawk Bisley .45 Colt with handloads using a 300-grain bullet. It has a 7-1/2" barrel and is easy to hit with at typical moose ranges down there in the willows and alders. In fact I have taken prairie dogs at close to 100 yards with it, so it shouldn't be too hard to hit a moose in the right place at closer ranges.
