View Full Version : bow speeds

07-19-2010, 03:20 PM
was wondering for you that use a chronograph how much variance do you get while shooting? I am getting 4-14 depending on when i am shooting. I am pretty sure i am not creeping any but very unsure of what is going on.

07-19-2010, 05:53 PM
With most of my old bows, I'd get a 4-7 fps variance. With my "09 Firecat, I'm actually getting a 0.4 variance. That's for a 6 shot string. Can't belive it's that close, but I have checked it several times. Shooting 317.8-318.2 for 6 arrows.

07-19-2010, 09:48 PM
I am getting 4-14 depending on when i am shooting

In the same session you get 4 to 14 fps difference or you get the variance on different day's that you shoot? Lighting conditions can effect it but so can the individual quality of the bow.

07-20-2010, 06:33 AM
My chronograph rounds off to whole numbers, and during a series of 10-20 shots, I'll typically see a couple shots +/-2 fps off my average.
I know my complete arrows are not identical in weight, varying up to 4-5 grains for about 1fps of that rounded number, and my draw/release may not be 100% exact every time, then the bow itself will probably have a little difference each shot.

I've checked a couple times to see what effect big temp/humidity changes might have.....like home during hot/dry mid July at 2700-3000 ft vs couple times I checked to see what happens during a cold/snowy late Nov hunt in the mtns at 6000+ ft, and seen about 5fps lower

Have seen some shots that dropped +/-10fps low, but that was often me punching the shoot and letting up just a little right at release, or the battery and/or lighting was getting weak and throwing some random off numbers.

07-20-2010, 04:31 PM
my readings are on different days with a lot different temp.

07-20-2010, 06:02 PM
My target arrows are real close for weight, not varying more than 1 gr from lightest to heaviest. Readings might vary 1 fps, but then a lot of times I get the same reading and/or "Dup" showing. Anything beyonds this and I re-test and usually the reading falls in with the rest. Of course centering to the chronograph, the same distance and aiming at the same spot throughout gives better results.

07-20-2010, 11:05 PM
my readings are on different days with a lot different temp.

Ahh, not in the same session. Lighting and or temp could be the culprit. ProChrono?

07-21-2010, 01:43 PM
ya the pro chrono are they a little touchy on lighting