I know I have seen pics of guns with 2 mags side by side under them. When I went looking for pics I couldn't find any. Anybody got any links to pics showing this? Thanks. Oh, and BTW, how does this work?
I'm more familiar with the side-by-side mags that hold one of the mags inverted with respect to the other. Military forces used to do this with electrical tape. They're offset and inverted do the bottom of one magazine is just short of the mag-well when the other one is installed. Allows for a quick release, flip, insert once you're practiced, and the mags are much closer together.
What you're looking for is called a "Magazine coupler"