The Tueller Drill is a self-defense training exercise to prepare against a short-range knife attack when armed only with a holstered handgun. One would think that a gun beats a knife every time. With superior weaponry, the fight should be easily won. But Sergeant Dennis Tueller, of the Salt Lake City, Utah Police Department, showed that it was not that simple. A common test of handgun skill was to start with ones hands at shoulder level with a holstered gun and place two shots on a target 7 yards away within 1.5 seconds. Typically, those trained with handguns can complete the drill in 1.31.4 seconds, although some have managed the task in less than one second. Sgt. Tueller wondered how quickly an attacker with a knife could cover those same 21 feet. So he measured as volunteers raced to stab the target. He determined that it could be done in 1.5 seconds. These results were first published as an article in S.W.A.T. Magazine in 1983 and in a police training video by the same title, How Close is Too Close? A defender with a gun has a dilemma. If he waits until the attacker is definitely within striking range so there is no question about motives, he risks injury and even death. The Tueller experiments quantified a danger zone where an attacker presented a clear threat. Please keep in mind that the gun draws were done with an open carry, non-retention holster. Concealed carry adds to the time required dramatically. Perhaps fatally so. Racking the slide to chamber a round takes time, precious time that one may not be able to concede and survive. It also allows for the possibility of short-stroking, stove pipe or failure to feed. All unacceptable. If I unholster my firearm I'm preparing to shoot. Not brandish, persuade, intimidate, or cajole. If the situation still warrants firing after drawing, I shall do so. Racking a shotgun slide in a home defense is generally frowned on as an intimidation tactic as well. Racking the slide to put a weapon into operational mode in the face of danger is not a viable option for me. The 1911 platform is my favorite. At the range. I salute those who practice so often that swipe the safety/muscle memory is automatic. I can't, in my mind, allow for the possibility that I may miss/fail at disengaging the safety at a critical time so I'm a single action/double action kind of guy. I'll even throw in "safe action" for us Glockaholics. Rack the slide? No way.