Rifles carried by both actors/hunters.

I have watched the movie several times and my favorite scenes are when both actors are shown carrying 8 bore/8 gauge double barreled rifles with external hammers and jones under levers to open them. These type rifles fired black powder and were used by big game hunters before the invention of smokeless powders. The rifles weighed around 15 pounds and fired about 270 grains of blackpowder. The bullets weighed about 1180 grains. This type rifle now is worth about $35,000 as they are not being made anymore.