Letter: D

A type of revolver in which the rotation of the cylinder, cocking and firing are performed by a single pull of the trigger. Most Double Action revolvers can also be fired in the single action mode by manually cocking the hammer.

A shotgun with two barrels adjacent to each other in the horizontal plane (See Side-by Side). If arranged vertically, it is usually termed an “over/under” shotgun.

A propellant composed of colloided nitrocellulose and nitroglycerin as its base as opposed to single base powder which has colloided nitrocellulose only as its base material. The percentage of nitroglycerin added ranges from a low of 3% to a high of 39%.

A trigger which has two distinctive pull characteristics. The first or take-up stage is usually long and light in pull force; the second stage having a short but distinct increase in the pull force required to discharge the firearm.

An arrangement of two triggers in which the actuation of one trigger presets the second resulting in a light trigger pull of the latter.

A term used for firearms having two barrels and a separate trigger for the discharge of each. This term does not apply to firearms with double set triggers.

Two barrels in a firearm mounted to one frame. Can be vertically (“over-under”)or horizontally (“side-by-side”) aligned.

A two-barrel firearm, usually side by side. Also known as Double Barrel or Double.

Simultaneous discharge of both barrels of a double-gun with a single pull of the trigger.

A pattern whose central area has few or no pellet hits.