When faced with weapons in a street fight (or with street fights in general, for that matter), your best bet is to run away. No matter how skilled you are at Brazilian Jiu-Jitsu, streets aren’t the same as training mats. However, if you absolutely must engage with the other side (i.e. you can’t run away nor deescalate the situation), your training might save your life.
It’s precisely for this reason that Tim Kennedy – BJJ black belt, Strikeforce and UFC veteran, as well as a Green Beret and Special Forces Ranger – teaches how to use BJJ techniques for weapon takeaway.

BJJ TECHNIQUES FOR WEAPON TAKEAWAY, BY TIM KENNEDY

Tim Kennedy emphasizes that you first have to gain an overpowering position against the other person. For instance, being in Closed Guard isn’t good; you’d be much better off gaining Side Control or Mount.
From there, you need to utilize your Kimuras and Americanas. In simple terms: if the other person’s arm (with their weapon) is pointing in the direction where their head is, you need to use the Americana… And if it’s pointing in the general direction of their hips, you need to go for the Kimura.

Naturally, when it comes to weapon takeaway, you need to use your gripping arm to control the weapon, not the wrist. And you need to apply this technique in such a way that you’ll be manipulating the person’s fingers and wrist; so as to disable them from being able to hold the gun or the knife.
Watch the video below for more detail and keep in mind that Kennedy is more then a well-trained and a well-experienced individual. And that most, if not all, street altercations can be evaded.

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