My understaning of the H&R/NEF slug gun is that it is the shotgun frame, and is the weakest of their various frames. They will not rebarrel it to a rifle caliber, but will rebarrel the rifle offering to a slug. If your going to do some heavy experimenting, you may want to consdier a high power centerfire, and get it rebarreled, or start with a Huntsman combo that includes a slug barrel on a rifle action.
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