This is what I have. Rem. 870LW, 28" fixed full choke. First letter of serial number is 'S', last letter of serial number is 'K'. It has a 2 3/4" inch chamber. My question is, does Rem. make a barrel with a 3" chamber, screw in choke, vent rib for this gun? One more thing, its a 20 gauge. Would like to make it turkey gun for granddaughter and grandson. As is, it does not pattern good at thirty yards with lead number 6 shot. Any information is greatly appricated. Cluck