KE formula

[SMOLT333]

My bows Ke is 56ft. lb. What would it be at 20, 30, 40, and 50 yds. Is there a formula for this or does one have to shoot through a cronograph.

[bowhunterbruce]

far to many variables to formulate, arrow weight, being the biggest factor and right up thier with draw length. quickest and easiest is through a chrony
bhb

[Ghengis Khandrey]

You can use this table to calculate your arrow speed, which use can then use to calculate KE



Arrow Speeds Without a Chronograph (Field Test)
1. Start by shooting a group with your bow at a target from 20 yards using your 20 yard pin.
2. Mark the center of your group.
3. Next, shoot from 40 yards , still using your 20 yard pin and aiming at the same point on the target as before.
4. Mark the center of this group.
5. Finally, measure the distance between the two marks.
6.Refer to the numbers below for your arrow speed.
Approximate Arrow Speed (fps) Spread between 20 & 40 yard groups (inches)

220 = 28.7
240 = 24.2
300 = 15.5
260 = 20.6
320 = 13.6
330 = 12.8

[knockturnal]

Download a program called The Archery Program Pro. you get 10 free trail uses. Plug in your info and it will spit out everything you could wish for.

[Riverbc]

http://backcountrybowhunting.com/articles/calc/

[Stéphane]

I used that website for all the formulas regarding archery. http://www.stickemarchery.com/stickemcart/archery-calculators.aspx

I heard someone telling me that nothing beats shooting for actual real useful inputs. I agree ;)

[knockturnal]

Those are both great but do not calculate KE at a distance.

[Riverbc]

Those are both great but do not calculate KE at a distance.

you are correct...I glanced the OP's question too quickly......I asked the same question a year and a half ago. http://www.huntingbc.ca/forum/showthread.php?68137-Kinetic-Energy-and-Arrow-Speed-Measurements&highlight=energy

[.330 Dakota]

All ya gotta do is poke a hole in it,,,accuracy is the most important thing

[SMOLT333]

Thanks for all the comments,the only accurate way is to shoot through a chronograph at different yards. I will get one when I get home from holidays and then will post my results. Due to a shoulder injury a few years ago, I shoot a 50lb. PSE Evo,sweet bow to shoot.

[Stéphane]

Thanks for all the comments,the only accurate way is to shoot through a chronograph at different yards. I will get one when I get home from holidays and then will post my results. Due to a shoulder injury a few years ago, I shoot a 50lb. PSE Evo,sweet bow to shoot.
Actually, there might be a $0.99 solution: http://www.youtube.com/watch?v=LfnQ884zFlM
Pretty cheap solution. Not sure how far it would pick up. I think I will buy that app just for fun. I can spare that much. ;)