from a standing start. It should not take you more than .35 second to react and shoot him (assuming you had gun 'on" him when this all began. U should have ALREADY DECIDED to fire if he moved at ALL towards you. there thus should not BE any "recognition-interval in such a scenario. Either he submits INSTANTLY, or you start firing. You dont really have any other realistic choice, unless you are Bruce Lee, or also have a good "stick" and skill with it.
He has to take TWO steps to do CRAP to you with a knife, short club, etc, from 10 ft away from you (toe to toe) in the OTHER .50 second,(second step IS faster) you SHOULD have shot him ANOTHER 2-3 times, or once more to the chest,and then BRAINED him, and you COULD have taken at LEAST one step backwards, "buying" yourself yet another .20- .30 second, (and thus, 1-more shot into him.)
He has to take TWO steps to do CRAP to you with a knife, short club, etc, from 10 ft away from you (toe to toe) in the OTHER .50 second,(second step IS faster) you SHOULD have shot him ANOTHER 2-3 times, or once more to the chest,and then BRAINED him, and you COULD have taken at LEAST one step backwards, "buying" yourself yet another .20- .30 second, (and thus, 1-more shot into him.)