These are all good suggestions...here's another....consider spending a few bucks to buy a rifled choke tube and shoot sabots. I hunted with an 870 12 g for years with this set-up...Winchester 2 3/4" sabots worked best for me but there are a bunch on the market to choose from. I got "pie-plate" accuracy with my at 80-100 yard ranges pretty easily after some practice.
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