First American made 20 ga

[Captain Bob]

Maynard made and offered replacement 20ga barrels for their rifles and they cataloged purpose made complete single shot shotguns as well. The 20ga barrels which drop easily into their 1882 actions were the culmination of their design and marketing scheme of offering shotgun barrels for their rifle system which began before the Civil War with their external percussion ignition models. See the mention and illustration of Maynard style externally primed cartridge shell in TPS.