The Tactical Reload: Worth learning or not?
Let’s visit that bane of competition shooters, law enforcement qualification courses, and ‘operator’ training schools. That’s right, the tactical reload.
What is it?
To put it country simple, a tactical reload is removing a magazine from your firearm (rifle or pistol) that you have fired some rounds from (but not all) and replacing it with a full magazine. You then keep the partially loaded magazine as a spare. This is different from an emergency reload where you are dropping an empty mag to the ground, then slamming home a full one in its place and charging the firearm.
Why use it?
In theory, the concept is that during a lull in a gunfight, such as while hiding behind cover/concealment and/or no active threats are engaging you, you pop out the mag you are working on and insert a fresh one. This allows you to resume the engagement with a fully loaded firearm.
The practice, this is at best a military or tactical team tactic that is practiced in fire-team sized groups, with 2-3 members returning fire or actively covering, while 1-2 members are reloading. In a personal defense scenario, private security, or solo law enforcement setting where you are alone, it is not as much of a viable option.
About the only exception to this may be for if you have a gun with a very short magazine capacity (say an LCP or LC380) and you get a few rounds off then want to top off to be ready for if the situation evolves from there.

(You have to practice swapping those mags around and seriously train for this before ever attempting to do so in the real world. In practice, its best to use an unloaded weapon and empty mags or mags filled with snap caps– and then still keep the muzzle in a safe direction and your finger off the trigger)
However, is it worth a damn?

