sycril correctly states "...there was a study done that showed that if a knife man was armed and within 21 feet, he will be able to attack a gun man with the g

sycril correctly states "...there was a study done that showed that if a knife man was armed and within 21 feet, he will be able to attack a gun man with the gun in the harness." This is commonly referred to as the "Tueller Drill", after a trainer who first published the phenomenon: "How Close is Too Close?" by Dennis Tueller: http://www.theppsc.org/Staff_Views/Tueller/How.Close.htm http://www.theppsc.org/Staff_Views/Tueller/How.Close.htm Interpretations of Tueller's findings vary a great deal depending on the role one plays in an interaction and one's intent. For example, one might conclude that police should e.g., "shoot anyone within 21 feet who has a knife.", "One shot and they're out of action." or "Anyone outside of 21 feet and carrying a knife can be disregarded." and so on. But those 3 statements are not necessarily true and one must analyze further: "Re-Thinking the 21-Foot Rule": http://www.hendonpub.com/resources/article_archive/results/details?id=3947 http://www.hendonpub.com/resources/article_archive/results/d... "The Tueller Drill Myth: Why The 21 Foot Rule Isn’t a Rule At All": http://www.itstactical.com/warcom/firearms/the-tueller-drill-myth-why-the-21-foot-rule-isnt-a-rule-at-all/ http://www.itstactical.com/warcom/firearms/the-tueller-drill... Google discussion of the Tueller Drill: https://www.google.com/search?q=tueller+drill&client=opera&hs=OzY&channel=suggest&gbv=2&sei=hg0FWNKUIoWijwT2sY6YAw https://www.google.com/search?q=tueller+drill&client=opera&h... It is quite astonishing how a simple experiment has revised thought about the old adage "Don't bring a knife to a gunfight!" Indeed it appears that within the 21 foot range, someone without a knife could be effectively unarmed (even if they have a gun).