PETER THEOBALD says:
I have always maintained that it is not a good idea to fire at birds in a large group, or flock, and definitely not if it’s a really big flock of pigeons, by big I mean more than 100 birds, as I am not convinced they come back after being scared in this way.
Maybe on those exceptional days when you have set up on the only source of food for miles around might pigeons try again later, but even then I doubt they will fall for it more than twice.
How many times have you been getting a really good shoot, when, for no apparent reason, the flight suddenly dries up?
I suggest this is because you have simply run out of birds. In other words, you have fired at all the pigeons using that field, and they have moved on to somewhere quieter.
If frightened birds continue along the flightline after being shot at, it is very rare, in my experience, for them to return to feed from that direction.