All that is cool, Mike. Except that the makers took into consideration the fact that short barrels would need a different angle of convergence to have them truly regulated. You are assuming, I assume ( grin), that all barrels, whether 26" or 32" are touching at the muzzles, and they are not. You are also assuming that all of them will center their pattern perfectly at the distance the dove was sitting on the fence, which they also do not. And furthermore, that Joe's extra full pattern is not going to be big enough to kill that dove on the edge of the pattern, even if it IS off because of the differing angles you speak of.

This is not all exact science. Bench rest rifles are, shotguns are not. As I alluded to earlier, there are probably more double guns that are NOT perfectly regulated, than there are those which are. The angle of convergence is calculated to be right with what the maker concludes will be the most likely load used in it. Loads on either end of the spectrum, heavier recoiling or lighter recoiling, will affect this.

One more time, why would a maker go to the trouble to build an exact angle of convergence into the barrels of a S x S and then bend them to parallel at the last few inches?

SRH

May God bless America and those who defend her.