Unknown 45 acp

45 ACP blank?
What have I got, who made it and what is its use?
Narrow extractor groove
IC over arrow
45%20acp%20IC%20arrow

45%20acp%20IC%20arrow%20b

Might it be a .455 auto blank? Appears to be semi rimmed.

.470 rim
.466
.465 c/m
.922 c/l

Can anyone identify the headstamp?

any ideas on headstamp and cartridge use?

Not me & can’t think what it might be even if I try putting pieces on the letters - F C with a broadarrow? makes no sense. I C I broadarrow, maybe? but not seen that ICI before, still missing an “I” & no hint of one either.

Has a very “Yugo” look to it. Some kind of tool or pyrotechnic cartridge?