To me the 20ga M50 is the winner. The 12s seem heavy and clunky to me.
Only ones I have extensive experience with was a set of 4 12s that were mounted on brackets that attached to the wing struts of a SuperCub. They were spring mounted with no stocks, had custom built 10 shot tube mags and were fired by 6v solenoids from 1949 Ford Flathead starters. Intended to be used for gunning wolves back in the 50’s or 60’s. Guy said his dad had them built and used them one season before dismounting them, he said they were dangerous as he’d get tunnel vision and forget he had to fly the plane. Pretty neat piece of history, I got them all working and fired them with the switches before they were donated to a museum.
I have a 59 in the closet I gave $10 for. Someday I’ll find a barrel and buttstock and get it running.
