There is a common misconception that if you just limit the number of rounds in a magazine then will significantly slow down an active shooter.Those of us well versed on reloading know this is not true. By doing tactical reloads (inserting a new magazine before your gun is completely empty) you can very, very quickly keep rounds in your firearm regardless of the number of rounds in the magazines.
In this video made by Indiana sheriffs they test multiple scenarios and show that there is little to no difference in the time it takes to fire 30 round from 2 15 round magazines, 3 10 round magazines and 5 6 round magazines. They also demonstrate shooting multiple revolvers (the fastest way to put 30 rounds down range in the video) and the reload time on an AR-15 rifle.
