.303 Blank?


I have an odd .303 that seems to be some kind of blank, tool, or propulsion cartridge. Brass case, copper primer, and the case mouth appears to be folded over and formed over a reddish wad. There are three stake crimps just below the case mouth. Seems a bit heavier than a standard blank.
Any ideas?


No ideas? John? Tony?


Jon - I have never seen anything like it in any caliber.

John Moss



Reminds me a little of the “Line Cutter” cartridges made with .45-70 cases. The ones I’ve seen have a cap like pot metal looking closure at the case mouth.

Just a WAG…





I think this is a later conversion by person or persons unknown.

It has three slit crimps at the neck which suggests it was loaded with a bullet at some time, as the crimps are not put in until after the bullet is inserted. I do not think it is an original British military experimental.

The GB case that it is loaded in is one of those made by an extrusion process as evidenced by the dots between the characters of the headstamp.



Thanks, Tony.
While what you say is most-likey possible, the closure constuction looks perfectly factory. The weight leads me to believe it was for some tool/non-firearm use.