Help Identify


#1

This cartridge and ignition system I am unfamiliar with. To it’s left is a 44 WCF for comparison. Anyone that could explain the ignition system and guns it fits and it’s moniker will help.
It’s Dimencions are:
Bullet Dia 0.435"
Rim Dia 0.510"
Base Dia 0.465"
Neck Dia 0.465"
Case Length 0.585"
OAL 0.975"




#2

Looks like a 12 mm Perrin,also called 12 mm French Tick rim to me.

It was intended for Lefaucheux weapons converted to CF ammunition.
Your round it’s inside primed


#3

That heavy rim suggests that this is a 12mm Perrin, a Civil War-era handgun cartridge designed in France by (who else?) Perrin. These had an internal centrefire priming system sort of like the US inside-primed cartridges, where the firing-pin could crush the base against an internal anvil to fire the round.