Sorry about the double.
My theory:
At one time there was a big concrete benifit in longer bbls due to the slow burn of black powder so everyone had them. When smokless powder came along it took several years for people to catch on that to burn all of the powder you only needed about 18". I still know people that think that longer bbls will shoot farther. So bbls got shorter because people really love short handy compact guns. I remember shooting skeet years ago when everyone was using 26" or 28 bbls. I think that 28 became the standard but there were plenty of 26"s. Sporting clays came along and since it was new, people were not persuaded by tradition to use the short bbls and since most people are much more likely to stop the swing rather than not being able to catch the bird the longer bbls became popular. I myself use a 32" for skeet.
This is a big benifit for those of you that like the shorter bbls ie. K-80 28"bbls are about 1/4 the price of a 32"
