One of my sons has a LC Smith 410 field grade double barrel (FW 94974, 28" matted rib full/modified, splinter forend, pistol grip, 2 triggers) . A few questions: 1) What is FW? 2) What is the date of mfg? 3) There is not much casehardening color visible, is that a big deal? 4) The gun is in great shape, what is a value range? Thanks!