Greener MK2 Harpoon Firearm cartridges

The Greener Light, MKII, Harpoon firearm was made by the well-known arms maker, Greener of England and distributed by the Navy Arms Co. here in the United States. This is the harpoon firearm that was fired off the bow of the boat in the 1975 “Jaws” movie. Yes
“We’re going to need a bigger boat”

Kynoch: The cartridges pictured below where produced by Kynoch of England for use in the European continent for the Light Green Harpoon firearm. Note the light green wax on the top of the cartridge to seal the cartridge water tight!


Navy Arms: The cartridges pictured below where produced by Navy Arms for use in the USA for Light Green Harpoon firearm. Note the the “Spl Tool” on the head stamp on the modified “WRA” Winchester Nickel plated “38 Special” case.


This is about all the information I have found on the firearm and cartridges, which is fairly sketchy, so please feel free to add more, if your more familiar with the subject.
Thank you,
Dave Call

This pattern of Greener harpoon blank has been listed in online auction in the UK, headstamp is Kynoch Greener. I don’t know which mark of gun it was for.


Picture is from the auction listing. The auction ends soon but will probably relist unless sold. … id=1556390

Interesting subject, Only have the converted Jarmann rifle loads “Hylseladdninger” from Raufoss.

The .38 Special harpoon blank were loaded using Norma cases (“From Swedish Components”). The modern ones by Navy Arms are not modified loadings but original tool blanks made in the 1950’s for the Ramset Super-Power Jobmaster nail driver.


Here is a description of the purpose of the original necked case loadings (10 gr. red crimp & 14 gr. green crimp) taken from Greener’s Light Model Harpoon Gun brochure:


I am familiar with the Kynoch cases and Navy Arms used Winchester (WRA) cases with a added
" Spl Tool" on the head stamp, but not familiar with the norma cases.
Anyone have a picture of the norma harpoon case?
Thanks for the added information.
Dave Call

Dave, what I meant to say is that the cases of the ones headstamped KYNOCH .38 SPECIAL were made by Norma.

Got you, thanks for clarifying.

These photos were sent to me by a friend in the UK. Note the handwritten notation for 10 grains 360 No.5 cordite, the same notation that is handwritten on the box shown by Pepper.



The small blanks appear to be Morris blanks which would have a certain believability because Greener made thousands of martini rifles in the Morris calibres for cadets and the growing interest in “miniature rifle” target shooting which evolved over time into the olympic sport of .22 rifle. … rifles.htm

Not what we would realistically call harpoon guns today they would probably stand better comparison with our concept of spearfishing. Shooting fish did occour, and it has come down to us with the expression “as easy as shooting fish in a barrel” something you still hear said but nobody understands. It also carries the implication that other ways were hard. See my comment about sport in the next paragraph.

I believe the practice was most prevelent on leaping salmon when it runs up the rivers, certainly in the UK. not many other fish that would be worth buying a gun for. I also believe it was done primarily for sport rather than economic necessity as a net would be more practicable and cheaper.

(footnote; that website is an excellent source of reference material. Certainly for my kind of stuff. Those of you who save reference sites I would commend it to you. Skip to the homepage and see what I mean)

The necked harpoon blanks pictured are somewhat larger than the morris blanks. I have seen them listed as a .300 harpoon blank which would at least roughly (without measuring one) match the diameter of the necked section.

Even if the dimensions are different the proportions look very morris like with that long neck. It makes you wonder why they would do it that way for a mere blank. Unless there was a bulleted round, maybe one which never made it off the drawing board, that served as the inspiration but is now lost.
It would have to be bigger than a standard Morris anyway if they are talking about 10grns of cordite. standard for a 297/230 is around 3-4 grains.
Have you noticed how Greeners seemed to like their stepped cartridges?

A Greener harpoon blank measures at the base: .377, a 297/230 measures at the base: .296
The harpoon blank appears to be similar to the .38 S&W special case

Maybe the long neck (and matching chamber) is to prevent chambering and firing of other ammunition in the harpoon rifle?
It looks like this chamber shape would prevent most, if not all, of the .38 rimmed revolver cartridges being chambered.
This could be for safety or proprietary reasons?
The brochure posted by Fede states that the blanks are ‘only available from Greener’ so maybe they were trying to be the only manufacturer of the blanks by having a unique case design.

Pepper, it looks like you just need the harpoons to go with that collection of blanks!

Maybe the long neck (and matching chamber) is to prevent chambering and firing of other ammunition in the harpoon rifle?

That was certainly the thinking with their 14bore riot gun built on the same martini action. Probably broadly within the same time frame, and another stepped case interestingly.

The brochure posted by Fede states that the blanks are ‘only available from Greener’ so maybe they were trying to be the only manufacturer of the blanks by having a unique case design.

That strategy ran throughout the whole of the British gun trade of the time and explains the plethora of bespoke calibres by the different British makers.
Its the only explaination in a lot of instances when you consider some were just rebranded military calibres. So I would say yes without doubt.

I am interested by what is also hand written on that box. .360 and no 5. There was a .360 garden gun cartridge which would have been about no 5 in the numbering sequence they employed for these cartridges. However, the rim thickness is far too thick on the pictured blanks for them to have been based on a shotgun cartridge.

Vince, it’s not .360 it is 360 without the period.
I’ll ask my friend if he knows precisely what the notation means. He said it would have been written on the boxes by Kynoch not Greener.

The “.360 No. 5 Cordite” or “No. 5 Cordite” was a powder used by Kynoch for their .360 No. 5 and .380 Long cartridges. It was named like that because it was probably developed specifically for the .360 No. 5, like was the “Short Morris Cordite”, “Sherwood Cordite”, etc.

Details of the harpoon gun chamber markings: