As someone in the comments pointed out, he isn't loading it. He is unloading it and catching the shells so he doesn't have to pick them up off the ground because he's an old man.

You can clearly see this in the video, he is cycling the action to eject the unused shells and catching them as they come out.

Of course I am no fan of Weirmacht Walz but this is the funniest attempt at a dunk by a supposed gun safety advocacy group.

Tim Walz caught on tape calling a magazine a clip

This is the dumbest timeline

Real hunters are loaded and drive around in golf carts to the deer tied down so they can unload on them.