Energy at range.

[Billy Goat]

I have started playing around with a few different shaft weights. Kinda getting late to change anything but I got curious and wanted to play a little.

Has anyone, or does anyone know where information has been posted on retained velocity? I'm thinking of setting my Chrono up and getting velocity at 50 yards. Trying to determine retained energy. Just wondering if the information is out there already and I haven't found it. Not opposed to trying it. Maybe I could replicate someone else's results.

I have read the archery report article but they only experimented to 20 yards. Thinking I want to know what happens at 40+.

 

[Beendare]

I've seen it somewhere...maybe on Archery report. I saw a test on a medieval armor that did something like this too....but it came down to the BH.

We know an arrow is deadly about as far as we can shoot them......and we know the heavier arrow carries its energy longer..........anything in between is gravy.

We can improve arrow performance a bunch of different ways...thus its not critical info.

 

[5MilesBack]

I've seen ballistic calculators that will calculate your speed at specific yardages, then you can figure energy etc, from there. I know when I did it with an older setup, I still had more KE at 100 yards than most guys do at the bow. IIRC it was around 77 ft/lbs, and that was with a 500+ grain arrow.

I've shot through a chrono out to 50 to verify their numbers, and they were really close.

 

[Billy Goat]

I'm getting ready to play around a bit. Started setting things up a little today.

I have nothing to gain or loose in this. I just have curiosity. My setup is proven. But since I always cruise postings to find info I will put things out there for those who want to do their own research. See what is verified. Hopefully give data points for people to make their own decisions.

 

[Beendare]

All I ask....is that you post a photo of your Chrono when you shoot it...../grin

Best of luck with your research

 

[Btaylor]

All I ask....is that you post a photo of your Chrono when you shoot it...../grin

Best of luck with your research

Was thinking along those lines too. I could put 5 in a baseball at that range then set a chrono up and the first arrow would most likely go right through the read out screen. LOL

 

[5MilesBack]

The opening on chronos is like the size of the killzone on an elk.......shouldn't have any problems not hitting it. Or shoot in the shade and remove the sunshade altogether from it. Either way shouldn't be an issue.

 

[roadrunner]

This is a pic of what I did what you're going to do. Chrono was set up about 3 or 4 feet from the target, shot distance measured from the chrono. Anything after 40 is extrapolated.

 

[Tilzbow]

I’ve done this when making sight tapes and it’s not easy to get good readouts on the chrono at 50 yards. I’m not sure if it’s the placement of the arrow, the angle of the arrow, shooting outside and the sun’s angle or a combination of all three.

In any case, once I got a few speeds registered at longer ranges, I found the speed I registered on the chrono yards was within 1 FPS of the speed calculated by the TAPro system I use for sight tapes at the same distance when I inputted all data including; actual speed through the chrono at the bow, arrow weight, vane height, point weight, etc so I quit shooting through the chrono at longer ranges. This has been the case with a few different setups. Once arrow information is inputted, The TAPro then calculates the other information you’re looking for all the way out past 100 yards. I bought the other, more popular, sight tape program system and tried it but I can’t remember if it provided the same information.

 

[Billy Goat]

So finally have time to post a few numbers. I had 3 different arrow configurations. My light arrow was a Maxima Hunter 350 with 100 grain point. My heaviest arrow was a Maxima Hunter 450 with 50 grain brass insert and 125 grain point. Also had a Maxima 450 cut 1" longer with only 100 grain point with the 50 grain insert. Had 3 of each arrow. My numbers are averaging the 3 of each together.

Maxima Hunter 350 cut 27.125 c/c . Cx insert. Cx bulldog nock collar. Cx nock. 3- 3" fusion vanes. 100 grain field tip. Total arrow weight - 391.5 grains.

Velocity 3' from the front of the riser - 313.7 fps.
Velocity 65 yards from the archers position - 280.1 fps

Maxima Hunter 450 cut 28.75 c/c. Cx nock. Easton 50 grain brass insert. 3- 3" fusion vanes. 100 grain field point. 463.4 grains.

Velocity 3' from the front of the riser - 290.5 fps
Velocity 65 yards from the archers position - 263.0 fps

Maxima Hunter 450 cut 27.75 c/c. Cx nock. Easton 50 grain brass insert. 3-3" fusion vanes. 125 grain field point. 482.0 grains.

Velocity 3' from the front of the riser - 285.4 fps
Velocity 65 yards from the archers position - 259.3 fps.

If someone wants to run those numbers through a program to check the accuracy I would be curious to know.

I was doing several things at once while doing this. I was doing some accuracy testing and testing penetration between a few things.

My bow is a 2016 Hoyt carbon defiant turbo. Set @ 72# and 29" draw. Shooting was done through a shooting machine.

If anyone is interested I can post more information. Or they can p/m me and I can send more information through email. I tried to have this experiment be as even as possible to try to test the ballistic coefficient of the two arrows. That's why I only used the CX arrows.