The breech mechanism is cycled by an external lever below the receiver

Feeds cartridges, fires and ejects as long as trigger is depressed.

Side by side barrel or over and under

Shoot only one shot

Have 2 or more barrels in one firearms

A movable forearms is actuated which is parallel to the barrel

The same as auto loading rifles, the recoil action reloads the gun from the magazine.

Used by military on combat. This is seldom encountered by firearms examiner. The largest gun ever used in combat was Gustav gun.

These are known as freakish devices

Fire tear gas and other forms of disabling gasses

Breech closure is in line with the bore at all times

A muzzle-rifled at the last 2-3 inches of the barrel, used to spin the paradox bullet.

Made by the US government capable of firing .45 cartridges, single shot and smoothbore

Used in sending signals and used in seeing enemies in the dark

Designed for wild animals. It could be with the use of bullet of poison charge.

A light and portable machine gun

Loads, closes, fires and deloads single cartridge.

Loaded with more than one cartridge in the chamber.

The operated by means of sliding lever under the barrel

Homemade guns in various designs

Are used in hunting large fish

Requires a separate pull of trigger for each shot fired

Maybe used to drive stud, punch holes, and which are also capable of accudentally firing live ammunition