I have watched ZZ birds shot at Strathcona Range near Edmonton, Alberta. This was in 1982 and the USA Army Marksmanship International Trap and Skeet Team were there.
After practice one day, the organisers suggested the trap team challenge the skeet team at ZZ. Seems you need an International trap gun for that game, I think one would be ideal.
Or a box bird gun, near enough the same thing, is it not. or are box bird guns set up to shoot flatter?
Anyhow a skeet gun does not work too well, you need the tighter chokes. And ZZ is a lot of fun, not too many places to shoot the game, the centre of the target must be shot out of the whole target, which is a 6 blade fan,I think), revolved on a spindle of the thrower, the spindle is parallel to the ground, and when the fan is spinning at the right speed, a shaft pushes it off the spindle, and that fan flies all over. Seem to remember 4 machines in a row, perhaps someone can correct me.
Mike