I have a set of 20/.410 Briley Sidekicks that I am considering having converted into Companion tubes. I am wondering how much shorter than the barrel I can make them that the choke in the tube itself will still reliably control the pattern. I will be using them in two different 20 gauge guns and really don’t want to make either gun too barrel heavy because I want to use these for shooting sporting clays and I like the way they currently handle. I once had a set of 12/20 Companion tubes that were 15 inches long and they did great at skeet, but never worked well with tighter constrictions for sporting. I have heard of people using 26 inch tubes in 30 inch barrels with success. Therefore, I can assume that 4 inches shorter works. Wondering about going even shorter. Anyone have any practical experience on this?