Jeff, I' d guess around 1 in 10 for birds on the wing. If I actually practiced moving aerial shots with any degree of regularity, I' m sure that ratio would improve. I once watched an elderly fellow bust aspirin after aspirin out of the air with a recurve and flu-flu' s. It' s amazing what can be done with practice.

On aerial/bird shooting, there is an add in a 1950' s era archery magazine I have for a " shotgun" arrow. Some company took a standard flu-flu and mounted a canister full of small spikes on the front. The idea was that as the large fletchings quickly slowed the arrow, the spikes would exit the canister and travel outward in a " shot" pattern towards the bird. It seems that product lasted only as long as the arrow' s flight, though.

Perhaps you are referring to African " pellet bows" ? I read of them in a magazine about a year ago. Certain tribes in the African Bush make bows specifically for shooting pellets/stones. They fix a leather pouch to the center of their bowstrings, which they load up with single or multiple pellets. I remember they apparently do quite well with them.