I hope you don't intend to shoot those 3" Magnum Shells in your 2 3/4" L.C. Smith. If so, do us all a favor and save a great shotgun from certain destruction in the hands of the uneducated. I will gladly trade you a Mossberg 3" chambered gun for you to duck hunt with. Hopefully you will heed the advice posted by B. Miller. If not you may be eating through a straw the rest of your days.