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Wesley Chapel archer reinvents the arrow

TwisterNock is a spring-loaded mechanical notch on the end of the arrow. All arrows have nocks, but Hajari's is spring-loaded to make the arrow rotate as it is shot out of the bow.

"It spins the arrow right off the bat," said Hajari, a 50-year-old Wesley Chapel resident who develops hunting products for sale in stores and on his website, "You get accuracy and better speed."

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Arrow and kinetic energy

Jeff Hajari

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  This is one of the most argued topics in archery world. When it comes to penetration, we have many people coming out with their physics formula, talk about momentum, and speed verses weight. The problem is, most people don't realize that in all the calculus about kinetic energy, they are talking about mass as a concentrated mass, such as a bullet. When it comes to arrow, there is no concentrated mass, it is a linear mass, and that is why it won't work in the formula. You can take 2 arrows of the same weight, but different spine and FOC, and they act completely different and penetrate different into the target.

When it comes to arrow, it is all about how well and how quick that arrow is stabilized. All efforts by archers, to tune their bow and their arrows is to stabilize the arrow quicker.
A heavier arrow takes less abuse on the shot, due to added weight and heavier spine of the arrow. They stabilize quicker and penetrate better with less speed.
A lighter arrow takes more abuse on the shot, flex more and they are harder to stabilize specially at short distance. In flight they can recover faster than heavy arrow due to their greater speed and the greater force of drag caused by fletching.
TwisterNock helps the arrow spine reaction on the shot, reduces the flex and helps to stabilize the arrow quicker.
The faster you stabilize the arrow the more kinetic energy you deliver into the target.