In a 13" barrel, the 44 mag loaded with a slow powder like H110 would be a fine choice for distances out to 125 or so. You will get a significant velocity boost over the same cartridge from a revolver, and yet be more comfortable to shoot. In the Encore you could even go with the 454 Casull if you want more punch, but the shooter will also feel it. The 30-30 is no slouch either, but one of my favorite 13" Contender barrels is the 7-30 Waters. IMO the 7-08 and 308 are better suited to a little more barrel length to take advantage of the increased powder charge.

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