[fogof]

They address this at the end of the article

> Our calculations account for air drag and the effects of gravity.

> While the return velocity is dependent upon a number of factors, firing angle is extremely important. Bullets fired at an angle maintain their angular ballistic trajectory and are less likely to tumble, allowing them to pick up more speed on the way down.

You make a good point about the infographic showing a cartridge being fired, but as far as I can tell there is only one infographic on the page that actually shows this. These factors make me suspect that you didn't actually read the article to the end before criticizing it. "Intellectual rigor" indeed.