How to Easily Calculate Arrow Speed Without Using Chronograph

If you are a hunter than you understand that it not only takes practice but it also takes a bit of physics to make the arrows or bullets precise.

If you have a hunting obsession you might try tinkering with it to make the arrows from your bow more effective.

arrows

Photo by Eric Clem

Every bit of fine tuning can help you on your next hunting trip.

Little details, like arrow speed can help you and are important in achieving this goal.

Arrow speed is easy to calculate even without the proper equipment.

If you are currently lacking the use of a chronograph you can still determine the speed of your arrow.

If you know the FPS or feet per second of your current arrow, and it’s weight you can calculate the kinetic energy output of your bow.

This is great if you are looking for the penetration power of your rig.

Below is a method to help you determine just how fast your arrows are going when just using your bow and a simple target.

Arrow Drop Comparison

To get a fairly accurate measurement of your bow’s speed (FPS) you need to compare your arrow drop at two separate distances.

  1. Set the pin for 20 yards and shoot a group of arrows. Be sure to use good pin placement and focus on form. The more accurate the shot is the better your results will be.
  2. Be sure to mark the center of your group of arrows using a marker for later comparision.
  3. Now change your distance to 40 yards. Than shoot a different group of arrows. At the same point you marked. Be sure you use the same pin you used for the last distance (20 yards).
  4. Than mark the center of that group. Now simply measure the distance between the two marks. The mark for 40 yards and the mark for 20 yards. (make sure it’s in inches) Compare the result to the chart below.

Distance

FPS

28.7

220

24.2

240

20.6

260

17.7

280

15.5

300

13.6

320

12.8

330

While is not as accurate as the actual equipment.

Not having a chronograph should not stop you from getting an idea of your FPS.

Now you can simply calculate what your bow’s kinetic energy is from there.

You can then continue to fine tune your bow to get a much more precise reading.

In Conclusion:

When it comes to finding the arrow speed of your bow it just takes a bit of initiative to get it done. Yes, it is easier to do it with a Chronograph, but you can still get a precise reading without one!