Everyone knows how metal bottle caps click, but if you do it right, you can get it to click repeatedly.
There is a fine line between the pressure of your jaw and the pressure of you hands. You also have to experiment with the angle which you hold the bottle cap. Sometimes you can push a small dent into the cap but too much will cause you to have to place too much bite pressure onto the cap preventing it from bouncing back. You can do it without a dent, but a small dent can allow for it to become louder.
I can assure you that my brother is not biting the cap repeatedly to achieve the sound. He was practicing for about 30 minutes after we shot the video and he was steadily becoming faster and more consistent. If it was from biting, his jaw muscle would have been tired a long time ago.
Post time: Jun-14-2017