I stumbled across this picture of an odd 1911 drum magazine. It looks like is made of multiple 1911 magazines in a rotary style setup.
It sort of reminds me of the X-Rail for shotguns or the Nerf Pyragon where you have small internal magazines arranged in a circle and the assembly rotates as the first magazine is emptied.
Obviously this design did not catch on and now we have conventional snail drums.