ICI trapshooting 12

Military load ?
Manufacturing date ?

The answer to your question appears to be yes it it a civilian cartridge that has been bought and marked by the MOD.

A couple of theories come to mind but I am not going to speculate. Probably TonyE will know some thing about them.

Roll crimp, smokeless diamond and the headstamp would make it pre WW2 but I am not sure exactly when they dropped SD powder and went over to star crimp.

A bit interesting is no6 shot which is not really compatible with trap shooting. No7 or even no 8 shot is traditional trap shot size .

“Sixes” are for pigeons, rabbits and maybe (who knows?) birds or seagulls around an airport (?)

I’m nudging this one to get it back up to the top in the hope that somebody can add something to it.
I am pretty sure it is for birdscaring. In my garage I have a small steel ammo box (British) which I have had for some years and use it as a tool box.

On it is stencled “Cartridges 12bore birdscaring” and what I presume is a date 2/90. Today I would guess they would use blanks but in those days who knows?

E-K Trapshooting cartridges were just run of the mill although Grand Prix was probably by far the most popular. There is nothing to suggest it is in any way a special loading.

The cancelation rings are thought (by some) to be just that, now no longer an issue item (Broadarrow). These were often used to train aerial gunners who rode around in the back of a lorry, shooting at aerial targets. Trying to learn lead. The US also did something similar, but probably used trucks.

The Bird scare shells are for often for airport (or farm) use and are often a paper or plastic hull with an M-80 (M 60?) firecracker as payload & propelled by a small powder charge which also lit the M- 80 fuse. It went up & BOOM - scared the birds. If you pick one up you know as they are so light. Also usually have a pie crimp.