The history of this unusual firearm dates back to shortly after World War I, when the British ruled over very large portions of the planet and the sun never set on the British empire. In several colonies around the globe, the British set up police forces employing locals to handle ordinary law and order issues, with British army garrisons to put down major rebellions and uprisings. There came a need to equip the local police forces of countries like Egypt, India, Hong Kong etc., with weapons to put down riots and jail escape attempts, without the need to involve the local army garrison. Therefore, the British government issued a specification for a new firearm for these police forces.
The requirements of this new firearm type were a bit unusual. First, many of these police forces were not well trained or educated, therefore the firearms had to be extremely simple, sturdy and reliable. They were expected to need minimal maintenance. Since there was a chance that the guns could be used against the British troops themselves, the guns had to be short-range weapons and single-shot only. Another request was that the cartridges used for these firearms should not be easily available. That way, if the police forces decided to rebel themselves, the British garrison could easily take them on.
Greener police shotgun. Click on image to enlarge.
With these requirements in mind, the firm of W.W. Greener, a well known manufacturer of firearms from Birmingham, UK, came up with the Greener police shotgun. The action chosen for this firearm was the Greener improved Martini action that we studied a couple of years ago. This reliable action was known for its simplicity and ruggedness. It was in the Martini-Henry rifle since 1871 and the Martini-Henry rifle was already used by many local militaries, which meant that many locals would be familiar with it. In addition, the barrel, springs and action were made of heavy-duty steel for extra strength and durability. The wood stock extended all the way to the end of the barrel, to prevent damage to the barrel. In addition, note the solid steel nose cap at the muzzle end of the barrel in the picture above. This cap served as extra protection for the end of the muzzle, so even if the gun was placed vertically with the muzzle-end on the floor, the steel cap kept the barrel about 1/4" off the floor. In addition, a bayonet could be attached to the steel cap. The butt-end of the stock also had a steel plate at the end, so it could be used as a club. The stock also had a compartment to store cleaning tools. The barrel of this shotgun had no rifling, so it could only be used as a short range weapon and since it used the Martini action, the user would have to manually unload and reload a new cartridge, each time he desired to fire it. The cartridge that this shotgun was designed to fire was a proprietary 14-gauge shell manufactured by Kynoch Ltd.
The original Mark-I model of this shotgun was released in 1921, mainly to colonial police forces in Egypt. However, it was soon discovered that unauthorized users could use a smaller commonly available 16-gauge cartridge in this gun and stuff the extra space with paper. In response to this, Greener released the Mark-III model shotgun, which had some improvements to prevent this:
New improved cartridge for the Greener Police Shotgun Mark III
In this newer model, the shotgun chamber was altered to take an unusual shaped cartridge. The base of the cartridge was the same diameter as a 12 gauge cartridge, but the front of it was narrowed down to 14 gauge. With an unusual bottle-necked cartridge shape like this, this cartridge could not be used with any other firearm.
In addition, the striker of the shotgun was also modified so that it could only be used with these unusual cartridges. Instead of a normal needle shaped striker, the new striker on this shotgun was shaped like a trident, with the outer two prongs longer than the middle prong. Note that the base of the new cartridge has a deep circular groove around the primer cap. The reason for this groove is so that the two outer prongs fit into the groove and the shorter middle prong can strike the primer of the cartridge. Therefore, the Mark-III shotgun could not use any other ammunition, except for this type of cartridge. If any other cartridge was used, the two longer outer prongs of the striker would strike the base of the cartridge first and prevent the shorter middle prong from striking the primer.
The end result of this was a cartridge that could not be used on any other firearm and a shotgun that could only fire a particular cartridge type. The British authorities were very careful to issue these cartridges in very limited numbers (about two or three per person). Therefore, if criminals stole these weapons or if the local government revolted, these guns would be useful only while the ammunition was available for them.
A lot of these shotguns were issued to colonial police forces in Egypt, Malaya, Hong Kong etc. Some of them were imported into the US in the 1930s, to be used in prisons. Greener continued to manufacture these shotguns even after British colonial rule ended in many parts of the world, until about 1975 or so. Used examples can be found on sale even today.