Re: Mossberg 20 gauge for deer?
100 w/ the smoothbore is quite a stretch IMO. I'd imagine accuracy would fall off past 50. You can try and get a rifled barrel for it (can find them used cheap sometimes) or you can get a rifled choke which would at least help. On the cheap you could throw a set of fiberoptic sights on the smoothbore and try a few types of ammo and see what accuracy is like at different ranges.
I have a mossy 20 w rifled barrel, scope, etc. It shoots really well w Hornady STS slugs out to 100 (probably more but never shot farther than that).
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