FAQ Encore Rimfire Barrels MGM Encore rifle barrel CUSTOM MUZZLELOADER STOCK for THOMPSON CENTER HAWKEN 15/16 BARREL CHANNEL. New case features include an overall length of 1.71, a slightly rebated rim that is the same diameter as the 223 Remington, multiple SKUs of factory loaded ammunition, plus the benefit of reloadability with a plentiful supply of 35 caliber bullets.