Greetings all...Pardon if I step on toes here, or kick a subject that may already have been discussed, but I am working on an idea. We have all probably seen the .58/20 gauges of Pedrosoli in Cabelas, right? Well, I am a double shotgunner, and am cautiously entering the double rifle scene, both as a builder and user. There was a post in this forum dealing with converting a double SHOTGUN to a double RIFLE. I decided to post a different direction-Here is my approach-since rifles would invariably need to be a stronger overall gun, a shotgun barrel set obviously would mate to the inital action and stock, and perform MECHANICALLY-but my question is, would the shotgun be as handleable as a shotgun designed as a shotgun? I currently have used both 12 gauge English field guns, and light 28 gauges. I understand the motions of using a double rifle mimic those of the shotguns-pointability, target aquisition, and instinctive reactions. I also understand the bigger calibers require a heavier gun, but... If I were to invest in a set of guns, with interchangable barrels, proportionally, say a .500 NE with a 20 gauge set, and a .375 H and H with a 28 gauge set-would I get the best of all worlds, or would I be bastardizing both the performances to have something that did something else, but not as well as any singular function? I likely will not be able to afford such an investement in this lifetime, but believe the question a worty one to raise ( I am building a double 18 gauge Manton muzzleloader with potentially a pair of .50 barrels-but it is a SHOTGUN first). Any info is appreciated, and do tell me if I am waaaay off base here.