3in 50 Cal case cut to 9 5/16" length


A friend has a 1943 dated 3in 50 Cal case which has been trimmed to 9 5/16" (236mm) length so that it now resembles a short straight case.

The headstamp is:
(Curved, above primer): LOT NO 293 S.M.C.
(Straight, above primer): 9 - 1943
(Straight, below primer): 3inMK7-MOD.1 [over] 50 CAL
(Curved, above primer): NOT TO BE REFORMED

It also has the ink stampings:

SPDN T.S 43 3433

My friend was going to put this case into a load of scrap metal as he thought someone had cut it down. However, I had a look at it, and the trimming has been done very well. It has been lathe trimmed and had the edges of the case walls cut into small radii to remove the sharp edges.

Whoever cut it down made a very good job of it. This makes me think it may have been done in service for a reason. Were there ever any short cased blanks used for the 3" 50 Cal? The other thought i had was that it was cut so that it could be easily smuggled off a ship as a souvenir. I’m sure either Ray or Rick has mentioned before about having fired cases trimmed to ash tray length for souvenirs.

Does anyone have any ideas? It seems to well done and has too nice of a headstamp to go to be melted down for scrap.

Thanks for any info.


I have a 3" 50 cal. case that was trimmed down and used as a blank. I can measure it when I get home to see if the overall length is the same as your friend’s case, although I’m pretty sure mine is longer that what you stated above.



There were a lot of variations of the short cases aboard ship, in all calibers including 3"/50. They could be used as saluting cartridges, to test firing circuits, for clearing a bore of debris, for removing a tompion or muzzle cover in an emergency, etc. Or, it could be simply a souviner that somebody cut down. Since many were made by simply sawing off a full length case they would be hard to tell from a souviner.

And BTW, we NEVER smuggled anything off a ship. We liberated it. That’s a completely different thing altogether. ;)



Thanks for the replies. This case looks almost like it was made this length at the factory, as the trimmed neck is that neat. It seems to be just too good for a souvenir. Would the cases you mention that were used on board ship for various purposes have been trimmed and loaded on board ship?


Every medium to large size ship had a machine shop, including a lathe, so it would have been possible to make the short cases on board. Cartridges, such as blanks for saluting, were standard items received from armories or arsenals. Cases for such things as circuit testing or clearing a bore used a lock/combination primer but it is easy enough to convert a fired case to take the seperate primer. So there’s no reason why they could not have been “home made”.



Ray’s points are correct. However, since the case in question is ink stamped “SPDN T.S 43 3433” that indicates it was last loaded with a charge of non-flashless powder, so it was most likely a full charge round that was locallly cut down.

Cases were frequently cut down for ash trays (as most people smoked until the 1960s) or for whatever use someone thought handy- flower vase, umbrella stand, wine cooler, etc, etc, etc.

I agree that the purpose made 3"/50 blanks with the cut down cases were longer than 9 inches and most were also marked on the case with a new designation.

We will probably never know for sure, bit it is a neat souvenir anyway.


Here are some interesting details on the 3"/50 cal. blank ammunition taken from an ordnance pamphlet dated May 1943:


My case is 457mm long (just shy of 18 inches). It is headstamped:

N.G.F. 4. LOT 31
50 CAL
3IN MK 7 (anchor) J.J.N. 6-48

There is also a number “5” stamped at the very edge of the head.


Thanks for the replies. Even though it probably is a souvenir I will make sure it is saved from the scrap pile.


Something I forgot to ask originally:

Does the “NOT TO BE REFORMED” mean that this case was only intended for single use?

What was the reason that the case could only be used once and not reloaded?