
Originally Posted by
Sonny Thomas
Depending on the bow and draw length and weight speed can be as little or nothing and as much as 12 fps.
I went around and measured all my large single cams and dual cam bows. The first speed nock is right at 4 1/8" from the bottom axle. Additional nocks go up the string. Most have 2 speed nocks (brass string nocks) and covered with shrink tubes. One single cam bow has 3 speed nocks as a 4th and 5th didn't make a difference and began to tetter on giving a slightly slower speed. My wheel bows and a Command Cam bow do not have speed nocks as they proved useless - these cams are small.
When trying speed nocks it's a trial and error thing. When chronographing have it set where it won't be moved until done and make a mark on the floor for foot placement - same distance from chronograph each and every time. Understand, the arrow begins losing speed as soon as it leaves the string. Normal distance from the face of a chronograph is given as one arrow length from the tip of the arrow or that the arrow is clear of the bow before crossing the first sensor.