Brent,
A lot of people have tried to help you here, but they seem to be missing the validity of your question. Ignore the rudeness.
It is indeed possible to achieve greater than cylinder bore choke without any internal constriction whatsoever. As long as you go from a larger diameter to a smaller diameter you will achieve choke. It is called swaging and gunsmiths have been doing it for years. Whether it would achieve the same degree of pattern reduction as an internal choke remains to be seen. Historically fully swagged barrels were made before internal choke was commonly used. Your example where the bore diameter stayed the same would not achieve the desired result. Whether a gun with a small cylinder bore diameter would actually throw a tighter pattern than one with a large bore diameter is something that would need to be tested.












Last edited by volleyfire; 12/06/17 11:54 PM.