some calculations on arrow speed in relation to flight time

njxbow · Post by **njxbow** » Thu Oct 02, 2008 10:30 am

i had some time to figure out flight time of arrows traveling at different speeds to 30 yds if anyone is interested, i rounded the results to the nearest hundreth of a second:

350fps = .26 hundreths of a second flight time to 30 yds

325fps = .28 hundreths of a second flight time to 30 yds

300fps = .30 hundreths of a second flight time to 30 yds

i know the arrows do slow down on the way to the target but what suprised me is how little difference that arrow speed makes at hunting distances. an arrow only takes 4 hundreths of a second longer to travel 30 yds when traveling at 300fps versus 350fps.

brokebow · Post by **brokebow** » Thu Oct 02, 2008 10:35 am

Good info,I will spread that around at the bowshop this week. Jerry

hetichunter · Post by **hetichunter** » Thu Oct 02, 2008 10:35 am

Shhhh dont let all the bow manufactures find that out. Speed is what they all market!

mikej · Post by **mikej** » Thu Oct 02, 2008 10:58 am

thanks for the info

crazyfarmer · Post by **crazyfarmer** » Thu Oct 02, 2008 12:56 pm

LOL... thats one reason im not so much worried about speed, espically +- 10fpson my compound bow. Its still not enough time for the deer to jump if there is a 50fps difference.

good info

fuel80guy · Post by **fuel80guy** » Thu Oct 02, 2008 2:12 pm

Here is something that i read a while ago.
A deer can drop 14 inches in 1/3 of a second,,,im no mathemation but im more for a quiet bow than a loud fast banger,,,,am i wrong???

Bill T · Post by **Bill T** » Thu Oct 02, 2008 3:03 pm

You guys are only looking at one side of the issue here. The other two are; how long is the time period between when the deer hears the sound of the shot and the arrows arrival, and how fast will the deer react.
Measuring the actual time period that the deer can react is easy. Unfortunatly it's impossible to know how fast an individual deer can react. One constant regarding reaction speed is that no matter how fast the deer pulls up it's legs, physics limits the bodys downward travel to a constant accelleration. The part of the equation that is really in question is how long it takes for the deer to process the sound of the shot, decide to run, then pull it's legs in. I guess we'd have to be a deer to really understand that one!

Boo · Post by **Boo** » Thu Oct 02, 2008 3:19 pm

Bill T wrote:You guys are only looking at one side of the issue here. The other two are; how long is the time period between when the deer hears the sound of the shot and the arrows arrival, and how fast will the deer react.
Measuring the actual time period that the deer can react is easy. Unfortunatly it's impossible to know how fast an individual deer can react. One constant regarding reaction speed is that no matter how fast the deer pulls up it's legs, physics limits the bodys downward travel to a constant accelleration. The part of the equation that is really in question is how long it takes for the deer to process the sound of the shot, decide to run, then pull it's legs in. I guess we'd have to be a deer to really understand that one!

Bill, this is giving me a head ache!

Normous · Post by **Normous** » Thu Oct 02, 2008 3:55 pm

This is exactly why I prefer light,fast accurate arrows for deer hunting. I know I don't need alot of KE to pass through a deer, therefore I don't need heavy arrows. And I know deer can react quite fast. I can better the odds of a good hit with fast arrows. I also know that every deer that has had one of my arrows pass through has been hit exactly where I aim with my speedly little lightning death bolts.

njxbow · Post by **njxbow** » Thu Oct 02, 2008 4:37 pm

for kicks i figured out that sound will travel 30 yds in .08 hundreths of a second.

depending on a speed of 300-350fps, the sound of the shot will reach an animal .18 to .22 hundreths of a second before the arrow does which basically means at 30yds, an animal has about 2 tenths of a second to clear out of the way.

saxman · Post by **saxman** » Thu Oct 02, 2008 4:42 pm

Heck I coulda figured that out

I sypher pretty good
Them add on's and take away's aint so bad but thos gazzinta's really get me.

You know, 4 gazzinta 12 and 3 gazzinta 9
I have trouble with them

fuel80guy · Post by **fuel80guy** » Thu Oct 02, 2008 6:03 pm

Another side to the equation is that of light bolts versus heavy bolts.sure light bolts will travel faster but with less kinetic energy and they will not absorb as much noise from the bow. Whereas a heavier bolt will absorb more noise from the bow and also produce more kinetic energy.
This is why i use heavier bolts and oh yeah i aim low too.

Normous · Post by **Normous** » Thu Oct 02, 2008 6:31 pm

fuel80guy wrote:Another side to the equation is that of light bolts versus heavy bolts.sure light bolts will travel faster but with less kinetic energy and they will not absorb as much noise from the bow. Whereas a heavier bolt will absorb more noise from the bow and also produce more kinetic energy.
This is why i use heavier bolts and oh yeah i aim low too.

Add Boo string whiskers and a STS and you have the best of both worlds. Fast and Quiet.

saxman · Post by **saxman** » Fri Oct 03, 2008 8:19 am

The deer that I have shot with my Excals reacted to the shots alright
Exactly the way I wanted them to.
It was their LAST reaction.

Pydpiper · Post by **Pydpiper** » Fri Oct 03, 2008 8:23 am

enormous wrote: ..with my speedly little lightning death bolts.

Love it!