I have a 20 gauge 870 w/ factory modified choke. I inherited it from my dad. When I received the gun, the gun shop told me not to run slugs through it. Somebody else told me it should be fine, so I don't know? Contact the manufacturer and see what they say, at least that would be my advice. I need to do the same with Remingtom.
Good Luck,
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Good Luck,
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