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21 Foot Rule

The 21 foot rule is what was determined when a police dept in Utah wanted to know how close is too close for a knife wielding attacker to be. What they found was that the average person could could go 21 feet in 1.5 seconds from a stand still. This basically says if your attacker has a knife and is 21 feet away you better have your gun at the ready. The whole don't bring a knife to a gun fight is only true if the guy with the knife is at a greater distance. Below are some more statistics we must know about us and our attacker. 

The average person can run, from a standstill:

21ft = 1.5 seconds

32ft = 2.0 seconds

How long does it take you to realize you're being attacked?

1.5 - 3 seconds (this greatly depends on situational awareness)

There have been studies that show it takes police officers an average of 1-1.5 seconds to realize the suspect is attacking before the trigger is pulled even when they have them at gun point.

How long does it take you to draw your firearm and hit a well placed shot?

1.5 seconds for an experienced/well trained person

2.5 seconds for a new/less trained person

This is something you're going to have to practice and have someone time you. I suggest train until you get it under 2 seconds safely with a well COM shot.

The average "fight" left in a human before total "bleed out":

6 - 14 seconds

How much ground can an attacker cover before total "bleed out"?

6 seconds = 90ft / 30yrds

14 seconds = 210ft / 70yrds (2/3 of a football field)

A knife wielding attacker at contact distance can stab you 12-28 times before total "bleed out".

The average violent attacker:

25 year old male

These are statistics we must know to successfully defend ourselves against a violent attacker. We must not think that just because we we have a gun we are safe from an attack. Even if we have a gun and an attacker with a knife is within a certain distance he could get the upper hand on you.

Lets say you hear some commotion going on look to your left and see a guy running at you with a knife over his head to stab you. He's approximately 30ft from you, statistically it'll take you at least 1.5 seconds to realize your being attacked, between 1.5 - 2.5 seconds (but for this scenario lets say it takes you an even 2 seconds), and the attacker is already running at you so he can reach you in less than 2.0 seconds (but for this we'll say it's an even 2). So, he's running at you, you draw and shoot. Well, he is on top of you and you're actually 1.5 seconds behind the attacker. The good part about a human having 6 - 14 seconds before total "bleed out" is that you also have that time (since you have probably been stabbed) to continue to fight back. The bad part is that the attacker is at contact distance and if you don't hit a stop shot he can still stab you (even though you shot him) 12-28 times before he "bleeds out". You must be ready at all times if we intend on successfully defending ourselves against a violent attack. It's gonna be fast!

How Fast?

A real knife attack is likely to look like this

Defense Training CWP classes

With the attack above if you are armed you should have your gun out and ready to pull the trigger if you haven't already done so. This guy has a knife within 30ft so you would be well in your rights to defend yourself.


We must know this info to stay safe and train with it in mind. Our local Sheriff's Deputy's protocol's are to shoot an attacker with a lethal weapon that's not a firearm within 30 ft. This is a good rule to train by. Get to know your 30 ft mark and train with that in mind. Remember that police are open carrying as well so it's a little easier for them to draw their gun. To be successful at defending off an attack our Situational Awareness must be great at all times.

COM = Center of Mass

Stop Shot = A stop shot is hitting the attacker in a vital area that will actually stop him. The Spine, Head, or Hips are the few places that has the best chance of stopping an attacker.

Bleed out = The point where the body has lost so much blood that it can't continue to operate any longer.


Make sure to check out our other pages for more helpful topics.

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