Need Help in Identifying a Cartridge

I was going through a bunch of .455 Webley cartridges that I have the other day and noticed that one did not seem correct.
I measured the dimensions and it does not appear to be a Webley. Any assistance you could give in identifying the cartridge
would be greatly appreciated.

The dimensions are:

Rim Diameter: .500
OAL: 1.17
Case Dia.: .480
Bullet Dia.: .440
Case Length: .790
No Headstamp

Here are pictures.

I’d say it is a 45 Webley ( note 45 not 455), that is an american cartridge designed to be used in .455 Webley and 450 C.F. Revolvers

My sample ( hds REM -UMC 45 WEB) has exactly the same case/bullet shape and almost the same dimesnions as your round. My round case has a slightly longer length (.819"), but our rounds both match dimensional tolerances for the 45 Webley cartridge as reported on various texts

PIVI Thank you for your assistance. Greatly appreciated.