Alternative to a Chrony

[Yooper Bowyer]

I saw a guy on youtube measure the speed of a supersonic baseball using a highspeed camera and two posts in the ground.  Could a smartphone do the same thing for arrows?  I think so, because a 150 fps arrow travels 30 ft in .2 seconds.  This means a camera with at least 5 frames per second would be enough.

My idea is to place two stakes in the ground 30" apart and film an arrow shot straight over them.  All you have to do is note the time it takes it to travel between the two and do a little math.

This is harder than using a chrony, but a lot less expensive than the good ones, and probably more accurate than the cheap ones.

[eastcreekarchery]

There r apps that use the sound of the shot to measure speed that r probably easier.

[willie]

if the timing between frames is precise and repeatable, it could be accurate.  you might try a number of shots at full draw, and a number at a lesser draw to see if the slower arrows are distinguishable from the shot to shot variance at full draw

[PatM]

Saxton Pope used a stopwatch.

[Victor]

I used the Chrono Connect Mobile Lite app. This shows pretty plausible results.

[stuckinthemud]

I use the audio timer on phyphox, its a bit awkward but gives a plausible reading, you just need a good solid stand to hold the phone

[Whiskeyjet]

Audio recording software will be more precise. Free programs out there will be down to the millisecond. Make sure to allow time for the report to travel to your microphone at the speed of sound.

[Yooper Bowyer]

How do the audio measurements work?

[stuckinthemud]

Shoot a measured distance, the timer starts at "twang" and stops at "thump", gives you time and distance

[Selfbowman]

Shoot 9-10 grains per pound of draw. If the arrow goes220yds it’s a good bow.

[bownarra]

Shoot 9-10 grains per pound of draw. If the arrow goes220yds it’s a good bow.

Either buy a chrony or do this ^ 

[stuckinthemud]

Shoot 9-10 grains per pound of draw. If the arrow goes220yds it’s a good bow.

This only works if you use a good arrow

[Selfbowman]

If the fletchings are 2” or shorter and it’s spiked close it will get it down,

[HH~]

If you want the best available this is what you go with. Can set Doppler up for 5 preset distances. This will give you data of what your arrow is doing along its path and deceleration. Work up to 100yds. As it is a radar they are regulated as to how much power output you can have as a civilian application in uUSA. They running about $600 with shipping.

https://mylabradar.com/

Shawn~

[PatM]

Shoot 9-10 grains per pound of draw. If the arrow goes220yds it’s a good bow.

This only works if you use a good arrow

 Assume a good arrow is available.