How PeriSight Works
The simplest way to describe it is to consider the path of an arrow as it leaves the bow. The arrow follows a rising arc as it leaves the string, briefly levels out and then follows an increasingly shortening arc as it approaches the target, where it stops. Normal bow sights don’t look down the part of the curve that matters to the archer, where the target is, therefore are accurate at only two points as shown in Detail A (and only one of those points matter).
Normal Bow Sight Arrangement
The technique that archers have used for hundreds of years is to estimate the distance to the target and then raise the arrow so the trajectory delivers the arrow to the target. Obviously this took tremendous skill, attained by much practice. Sometime in the last hundred years, pin sights became the norm. A wonderful invention, the archer was now able to know exactly where there arrow would hit for a particular distance with the use of a pin sight. By stacking multiple pins, the archer could now have multiple points where they could count on an accurate shot. But any distance between those points was not accurate and still the error in estimating the distance to the target exists.
By raising the sight line with a periscopic device, the archer is able to look down the further side of the curve. As shown in Detail B, the accuracy zone or kill zone has increased substantially. Using this simple innovation, the PeriSight has been able to revolutionize bow shooting accuracy.
Improved Bow Sight Arrangement
How it works:
Let’s talk accuracy. Accuracy is a tolerance. The archer aims for the center point of any target, imagine the center of a circle. In reality, the arrow will likely not hit exactly in the center. Therefore, accuracy is defined by how much the arrow consistently misses the center point. This can be measured in a plus/minus value. For example, I am accurate with my bow to within +/- 2” at 20 yards. My personal accuracy degrades as I get farther from my target, and without better equipment or better form I will not improve on this. Your particular accuracy (tolerance) all depends on your target size and your expectations. When hunting white tail deer for example, if an archer can consistently put arrows into a circle the size of an 8” diameter paper plate, that hunter will have dinner on the table that night. That equals an accuracy of +/- 4”. That is 4” above center and 4” below center (elevation). Also if you want to get technical, it is also 4” to the left and right (windage), but with varying distance, we are only concerned with elevation. If you are hunting grouse, you want to be +/- 2”. Unless you expect a head shot, then you would want +/- .5” accuracy.
Now, let’s talk about kill zone. It is a simple concept. The kill zone is the range where you expect to take a shot at your target. The average distance that an archer can expect to take an eastern white tail deer is approximately 28 yards. Some will be closer, some further. The archer might want to set up their system with a 15-30 yard kill zone. That is as easy as it gets, right? Similarly to kill zone, the calibration distance is a simple concept. This is the (single) distance that you will sight-in your system. This calibration balances all of the trajectory theory constants with your bows variables and provides us with the best engineering compromise. So set up is very easy: a single “pin”, a single sight-in distance and you are ready to shoot.
Pure Instinct and No Guesswork.