12 gauge does very well for all aplications of a shotgun. The lightest loads all the was up to super duper magnums. Alot of bear guides like 'em with buckshot (or slugs) loads for back up guns. Slugs work well for deer and the turkey magnums are, well, good for the turks. The remington 870 turkey super magnum is an awesome choice. Long enough barrel for most applications. If you plan on shoting alot of sugs, get a rifled barrel as well.
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