FN of Belgium was working on 40x46SR in the late 1960s and developed there a row of different TP loads and at least 1 HE round.
Also there are 40x53(S)R but for them I have no approximate date, they could well be later made.
Is there any documentation on these FN loads available?
I assume they must have advertized these back in the time they were making them.
Photos of actual rounds or components are also welcome.
Here the only I have on the 40x46SR HE: