In multigun matches loading the shotgun is the one aspect that can really take up a lot of time. There are some really skilled people out there with some great shell manipulation, but the fastest method by far is the speed loader.
This plain and simple looking device, when properly used, can reload a shotgun in the blink of an eye.
Watch Jerry Miculek at last year’s FNH 3Gun stage 3 clean up with this speedloader. It is used at the end of the video. If you blink you will miss it.