If you’ve ever wanted to get a good look at the effects of different cartridges on calibrated ballistics gelatin for the sake of choosing a good defensive round, the Youtube channel by BrassFetcher, a ballistics testing outfit, is just the place to look. Here they go through different calibers, loads, brads and bullet weights so you can take a loot at the hard facts. Each video lists down characteristics of the ammunition being tested and the firearm from which the round is fired. This plus some light reading on how ballistics works should go a long way to helping you decide what loads you should be looking at for defensive carry. These are by no means the only resource on the ‘net for this kind of thing, but the results, methodology and process seems consistent, so you can quite reliably weigh one option against another. A little warning, though, you might spend a lot of time just watching these vids, so make sure your to-do list is clear before you head out.