I don't often just pass along links, but I read a couple articles recently that were so excellent and full of data I'm going to do that.
First is a test of shotgun patterns and effectiveness from Field and Stream. Totally worth a read.
Second, Andrew did some exhaustive testing of AR-15 muzzle brakes and flash hiders. It's broken into a Part 1 and a Part 2. This is amazing work. This is the same guy that a few months back did exhaustive testing on different ammo and barrel life in AR-15's. And also measured how noisy different pants are in his recent review. This guy rocks.
Anyway, I hope you enjoy those as much as I did. Stay safe out there!