I've got a 20Ga. Skeet grade M21 (which doesn't say "Skeet" on the floorplate, but the Cody letter calls it a Skeet Grade) - it does have the longer BT Skeet forearm. SN 316XX. 1955 Frame, according to Schwing It has two sets of barrels - 26" and 28", both with 3" chambers. The Cody letter doesn't call it a Special Order gun, but it did call for a stock with 1/4" cast off, so it obviously was ordered specifically