.303 British DA 1917 GP-B

I don’t know if this is a reload but I’ve never seen such a crimp, it is a set of 3 double vertical stabs.

Factory loaded “Gallery Practice Ball” by Dominion Arsenal.

So, you are saying that this is the original crimp?

Just examined about 25 of these with the GPB hs and they all have that crimp. The factory reloaded rounds with cancelled MkII, IV and VI hs lack the short vertical stamps on the crimp.