16 Gauge Shotguns are normally found with 2 3/4″chambers. with lengths of 18″ to 32″. Shotguns use many of the same actions as rifles—the pump-action, semi-automatic, and bolt-action. They also use a break-action as either a single barrel or double barrels. The double barrels can be arranged horizontally (side-by-side) or vertically (over-under).
There are four common types of shotgun actions:
*Break-action is the only type of Shotgun that can use the Adapters we make and sell
A 16–gauge shotguns bore is nominally 16.8 mm (0.662 in)