PETER THEOBALD says: Fast crossing or overhead birds always seem to be killed more cleanly because they tend to get caught in the shot string of an accurately placed shot.
A slow approaching woody does not present much of a target, so invariably gets hit in the wings, which brings it down but does not kill it.
The solution is to either use more choke, or, as I do, deliberately turn the bird and shoot it as a crosser.
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