Arrow Ballistics Calculator

Enter
Weight
In Grains

Enter
Speed
In Feet Per Sec

Kinetic Energy
Ft- Lb

Momentum
 LB.FT.-SEC





CLICK ON THE GRAPH TO VIEW LARGE IMAGE

All of the data for the graph was collected using the above calculator,
and is based on a high efficiency 60# Recurve Bow


Here are the actual formulas if you are interested in double checking the numbers


(1)
Bow efficiency was calculated based on 1 foot per second arrow speed deducted for every
5 grains of arrow weight added. 600gr / 10gpp  arrow weight is the center point of the chart.
Center point indicated by the 180 at bottom/center of the graph.
 

(2)
Minimum
arrow weight 400gr / 6.6gpp for the low weight, and 800gr / 13.34 for the high.
 

(3)
Speed
- 140fps for the lowest arrow speed, and 220fps for the highest arrow speed.
 

(4)
The Arrow Kinetic Energy does not start to drop off until above to 10 gpp area, and then only       slightly to the end.
 

(5)
The Arrow Momentum has some slight change, but it is so fractional, that it basically remains flat lined. This is due to the reduction in arrow speed as the arrow weight is increased.
The only way to have a significant momentum increase is to at very least maintain arrow speed.
 

(6)
The efficiency of the bow, whether increased, or decreased, will change the numbers/line gaps, but the incremental changes in the graph will remain the same proportionally.
 

The Vertical Dotted White Line is the point at 9.5 gpp.
This is the area I have always found to produce the best penetration,
and overall (combined) performance for me on my hunting rigs, and the graph shows me exactly why that is.
 

My Conclusion:
There are  only two ways to increase output/delivered energy of your arrow.

(1)
Increase bow draw weight, and/or bow efficiency to deliver more energy to the arrow.

(2)
Increase arrow weight, but this option forces you to increase the bow efficiency (IE: energy  applied to arrow)  proportionally the same to maintain arrow speed, or it's all a wash at best, or you lose energy at worse.


Hope you find this information useful