A clicker is an addition to a recurve archery bow. It’s most likely a springy piece of metal attached to the riser. The clicker hangs past the arrow rest/shelf.
An arrow fits under the clicker. As the archer reaches full draw, the arrow point will slip under the springy clicker and the archer hears the onomatopoeic sound of “click”. This signifies the archer has reached the right point to release. The clicker provides a high level of consistency. Many archers train around the “click” and integrate it into their shot sequence.
The clicker is also used as a draw length check. The position of the clicker is adjusted so that when the archer reaches full draw, the clicker just begins to slide down the arrow tip. When he is satisfied the shot is set up, he increases back tension. As back tension increases, the draw hand moves the bowstring and the arrow back, so that eventually the arrow slides out from under the clicker. The clicker slaps the riser and makes a noise, hence its name. Archers generally watch the clicker to see that the length of the draw is sufficient to place the clicker on the start of the slope of the arrow tip. After that, visual focus switches to aiming. The clicker facilitates the use of back tension, plus it discourages anticipation of the release because the archer is never quite sure when back tension will have increased enough to slide the arrow from under the clicker. For finger shooters, these are important advantages in setting up consistent and well executed shots. Most Olympic style shooters use one, but finger shooters in bowhunter class often are not allowed to use clickers.
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