[themason2011]

"This one had the chamber reamed out for 12 gauge (not by me) and has the rest of the barrel left in 14 gauge, so it acts kind of like a modified choke (dimensions are similar)."

I could be wrong, but I'm pretty sure the OPs Mk.III was never chambered for the bottle-necked 12/14g cartridge, but has always been a 12g. All of the Egyptian Police guns in 12/14g that I've seen, owned, & handled have the EG stamp on the right-hand side of the action, along with some Arabic script on the barrel & action. Greener Mk.IIIs were made in three chamberings; the straight-sided 14 1/2g (these are the ones which were sometimes used with paper-wrapped 16g ammo to overcome the loose fit), standard 12g, & the bottlenecked 12/14g. In addition to having a bottlenecked chamber, the 12/14g guns also had a three-pronged firing pin, the two outer prongs designed to fit in an annular groove at the rear of the cartridge, so that the central firing pin could reach the primer, this was another feature to make it more difficult for captured or stolen guns being able to be used with anything other than the unique ammunition designed solely for these guns.

Greener Police Shotgun Cartridge and Weapon (dave-cushman.net)

It's entirely possible that I'm wrong about it being an original 12/14 gauge. Of the limited info that I found online, I just saw that the vast majority of the mk3s were made in 12/14 gauge. Although I knew they did make standard 12 gauge, the stuff I read made it seem like that was very rare. For the price I found it, I figured there was no way it could be an original 12 gauge, but maybe it is! I also read that the Greener company still exists and will provide info on the origin of your gun if you pay them, but I just never got around to checking it out with them.

 

[john.k]

In fact 14g is not a big difference........a lot of competition guns are 14g ,using 12ga shells...............As a commercial gun ,the Greener must he proofed and have gauge and proof marks on the barrel made by the Birmingham proof house .

 

[DisasterDog]

As a commercial gun ,the Greener must he proofed and have gauge and proof marks on the barrel made by the Birmingham proof house .

The examples from @martin08 and myself are both proofed similarly with the “1-1/2 oz” (shot) marking. The “Tons per [ ]” marking on the OPs example didn’t come into use until 1954, and clearly shows it was proofed for 12 gauge 2-7/8” shells. I’ll dig out my GP in the morning for comparison, but they’ll probably nearly identical.

 

[DisasterDog]

I’ll dig out my GP in the morning for comparison, but they’ll probably nearly identical.

Not quite, only 2-3/4”:

 

[Edward Tinker]

Original ammunition for these is extremely uncommon, seen single rounds selling for ~$35.

Yes, I must have a different type

 

[DisasterDog]

Yes, I must have a different type
View attachment 4213853 View attachment 4213854 View attachment 4213855

Yep, that’s Pakistani .410 ball for the SMLE shotguns. The crates are neat but the ammo is most likely duds.

 

[X-Ring Services]

SteelSteed said: "Would be interesting to see how he made that due setup."

Here's some photos he posted on the British Militaria Forums site, but not sure if they're detailed enough:

Greener 12/14g made from MagTech 12g brass shotshells.

Top die is a LEE .577/.450 M-H that he got the outside dimensions from.

Finished product.

 

[DZ]

I listed my Egyptian Greener Police shotgun for sale yesterday on the trader section

 

[SteelSteed]

I’m cleaning a Greener and it is missing the middle barrel band. Does anyone have an idea where to get one? Is there another old rifle or shotgun that has a similar-enough profile to use?
Thanks,
T