I’ve always appreciated the underlying rationale in IDPA for doing all reloads from slide lock given the narrative frame of self-defense integral to the sport. It’s known beyond doubt that in a self-defense situation you’ll pull the trigger until the threat stops or the gun surprises you by running dry. You won’t be counting shots and be able to plan reloads in real life.
But on the day of the match, you’ll see it. A new competitor, a reasonable individual easily capable of counting to eleven, exposed to simulated stress of the match, having all of that melt away and mashing on the bang switch until the gun shocks them by running dry.
I’ve even done it myself somewhat recently. At the North Carolina Section USPSA match, I shot one stage with improperly inserted hearing protection, which I discovered after taking the first shot. As the sound of my splits and transitions filled my head and my mind raced for a solution other than toughing it out (I didn’t want to just stop and throw away one of nine stages in the match), I found myself mildly puzzled when my gun went to slide lock. Perforce, I reloaded it and then kept shooting only to again be vaguely baffled ten rounds later.
So there you have it. The science is settled.
Between watching people struggle with a tac-load, reloading with a round in the chamber and retaining the partially-empty magazine, and observing shooters at the Wake Action Pistol outlaw matches reload a gun not at slide lock for the first time, I’ve come to realize: most novice shooters don’t know how to top off a loaded gun.
The founders of IDPA created it with a panoply of different assumptions, among them the fact that people should practice slide lock reloads. But the fact of the matter is, every time the average person goes shooting, they practice empty-gun reloads. Shoot the gun to slide lock, put ten more bullets in the magazine, insert the magazine, rack the slide. That’s well understood.
The skill that competition fosters in this case is being cognizant of the loaded/unloaded status of the chamber of your gun, and acting accordingly. I’m not saying that, on the hierarchy of skills that might save your life in a gunfight that this is high on the list. But it can’t be denied that nobody needs to be taught how to reload an empty gun. But it is conceivable that quickly and efficiently topping off a partially-empty gun without racking a round out on the ground by force of habit is an unmitigated good that competition can force you to learn.