if the local LEO's show up about a complaint of a guy with a gun, and its obvious youve been shooting it "in public" you could easily be chargesd with discahrging a fire arm. Or violate local/state hunting laws because of the lower being a fire arm. And shrouding or shortening the barrel would make you in violation of the NFA act as soon as you mounted it to the lower.
SO be careful!
I think we'd need to see one tore down before we could offer advice on mods.
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