they're pretty useless in battle terms, although they can annoy and taunt
opponents, be used for celebrations, distractions, and masking flak and torps, and I
think TNF used it at one point for some reason (can't remember).

they're really expensive though, so dont use them much

I know that the first all purpose British twin turrets can use them but thats all I can
remember

you can get them from specific guns such as guns that can high angle to get the
shells just load up 'FC' shells check trainworld.us to get more info on htem