.50 caliber. 30" heavy wedge retained octagon barrel. SN: 892. Browned finish iron and brass furniture, half-stock with checkered wrist and raised cheek rest. Back action percussion lock marked "SLOTTER/& Co PHILA". Top flat of barrel also marked "SLOTTER/& Co PHILA" in a pyramid. Left breech flat marked "892/GAIN TWIST/WART". Equipped with double set triggers, fixed notch rear sight, dovetailed German silver front sight blade with steel base. Mountings include iron buttplate and toe plate, oval brass patchbox that is also marked "SLOTTER/& Co/PHILA" on its interior, a double finger spur brass triggers guard and brass nose cap and escutcheons for the single barrel wedge. Two additional iron ramrod pipes are secured to the barrel's underlug and contain a wooden ramrod. Heavy barrel measures 1.25" across the flats at the muzzle. A prototypical Plains Rifle in the form of the most successful of the St. Louis makers, executed by a Philadelphia gun making firm well known for producing their own versions of successful firearms designs, with Henry Deringer's pocket pistols being chief among them. The firm operated from roughly 1860-1868 and is better known for producing quality target rifles than heavy Plains Rifles. This is a very nice and rather uncommon example from the end of the percussion era.