The Impact of Arrow Speeds on Kinetic Energy
Basically, the kinetic energy is the type of energy which tells us how much energy a moving object possesses. Right now our point of concern is a moving arrow, and we are interested to know how the speed of our arrow determines the kinetic energy which in return reflects the impact of the arrow.
There is something called IBO rating labeled on the bow and it tells us about the standard speed of that certain arrow (be it 300 fps) but that’s the most confusing thing because that speed has been calculated under strict settings such as draw length of around 30 inches, weight of an arrow approaching 350 grains and draw weight set to 60 to 70 pounds. Then your arrow will be able to achieve its IBO speed otherwise less than that and keep in mind the kinetic energy relies on speed “the higher the speed the greater will be the kinetic energy”.
The Impact Of Arrow Weight On Kinetic Energy
Yet another significant factor affecting the kinetic energy and for the matter of fact, it goes similar like the arrow speed. The heavier arrow will definitely possess more kinetic energy, but it will lower down the accuracy of your arrow.
The weight of the arrow should be calculated keeping in view the weight of different things, for instance, Nock, vanes, shaft and tip. But always remember that the heavier arrow will eventually decrease the speed of it and then it’s up to you which you want the speed or weight? And don’t forget heavier one gives more kinetic energy to your arrow.
How To Calculate Kinetic Energy?
This is really simple just a piece of cake, as we have seen the kinetic energy entirely depends on two factors arrow weight and arrow speed so the formula of calculating the kinetic energy will involve these two factors (and it is advised to turn on your calculator).
We will be making some assumptions (based on reality though) suppose you have chosen an arrow of around 350 grains and under the strict settings of draw length, draw weight we have got the speed of the arrow to be around 270 FPS now it’s time to calculate how much kinetic energy our 350 grains of weight arrow will have.
(Weight of an arrow) x (speed of an arrow) x (speed of an arrow)/450240
Putting the values in above-mentioned formula yields the kinetic energy 56.66 ft-lbs but keep in mind this is calculated under certain settings of draw weight and length.
Kinetic Energy Deterioration Rate
The value which we have got in previously mentioned example (56.6 ft-lbs) but that kinetic energy is just for the point blank and you won’t encounter any target standing at the point blank so there will be some deterioration of your arrow’s energy. The rate at which this energy deteriorates has been calculated somewhere around 1.7 lbs per 10 yards or so let’s suppose if your target is waiting for you at the distance of 50 yards then the impact of your kinetic energy of your arrow will be around 5 x 1.7 = 8.5 and then subtract this value from the point blank kinetic energy which will give you 56.6-8.5= 48.1 ft-lbs.
How Much KE Do You Need To Take Down Game Animals?
That seemingly simple question requires some sort of explanation as the kinetic energy needed for taking down any animal depends on the size of the animal. It varies from animal to animal, for instance, small animals like rabbits, groundhog just requires less or around 25 ft-lbs of energy.
The kinetic energy of 25 to 40 ft-lbs should be there to knock down the animals like deer, dogs. For bears and elephants, you will certainly need a great burst of energy around 42 to 65 ft-lbs. don’t forget to hit the bull’s eye target and that will make your life easier as hitting the sensitive organs will bring down the giants as well with less kinetic energy.
Is More Kinetic Energy Always Better?
Of course not it depends on who you are and if you happen to be a hunter then you will certainly need heavy arrows that will in return give you small trajectory (gravity tries to bring it to the ground). But if you are to perform target shooting then the smaller weight of the arrow will do the job and you won’t need that much kinetic energy all you need is the accuracy.
The formulas used above and the calculations are just made as assumptions and they are taken after neglecting the factors like the weather out there, the technique of the shooting (varies from person to person). Suffice to say that this guideline should prove to be helpful for you in dealing with various important factors of arch shooting.