Short 2 pounder projectile

[SG500]

The attached show a regular 121 fuzed 2 pounder next to a short version.
The body of the short version is 4 inches long without the fuze.
The base is shown, as can be seen from the third photo there are tiny holes in the crimping groove, a total of 4 equidistant holes are in the groove. There is a base plate that cannot be removed.
The only clear stamping on the projectile is show in the third photo although these are very faint traces of stamping elsewhere on it.
The case is stamped 2pr AUTO mk A VSM. There is no date.
I don't know if the projectile is correct for the case.

Can anyone provide any information about this round please.

Dave.

 

[SG500]

Mmmm you've gone quiet on me
Just applying a bit of logic and guesswork, and ignoring the case its currently in, could it be a projectile for the 40 x 239 mk 5 aircraft gun round?
Appreciate that the only ones known (by me at least) are the ones with the 131 fuze, but from memory the driving band would be correct.
Thoughts anyone?
Dave.