Long Distance Shooting(Arrow Tests)

[Anvil]

I had the day off so I decided to do some simple arrows flight tests. Made some surprising observations. Using my Cari-Bow Silver Fox, 55# at 28”, 62”,  Dyna 97 padded loop string with two home made silencers. Each arrow was shot 5 times and an average was taken. The arrows were as follows, all were spined 70-75 and 29” BOP:
1) Tapered Sitka Spruce  160gr point, 3 - 5 ½” fletch – 544grs total weight.
2) Tapered Ash 160gr point, 3 - 5 ½” fletch – 642grs total weight.
3) Tapered Laminated Birch, 125gr point, 3 – 5” fletch – 745gr total weight.
4) Easton Legacy 2020, 175gr point, 3 - 5 ½” fletch – 607gr total weight.
Arrows 1, 2 and 3, despite the big weight difference all three traveled an average of 195yrds. Arrow 4, the aluminum averaged 215yrds.
My first surprise was that the heavy lam Birch arrow went the same distance as the lighter arrows. My guess is more mass = more momentum. It is noticeably slower at 20yrds. The biggest surprise was the 2020. I am hoping someone who reads this will have some insight because I am curious.
Thanks and God Bless.
Curt
 

[overbo]

My guess would be less paradox in the 2020,therefore it straightens to a true flight faster giving more final distance.

[mmgrode]

Hey Curt,
   hope you're doing well. Cool test. Arrow travel distance is directly proportional to the velocity with which it leaves the bow and the angle at which it is shot. Drag from air resistance also needs to be taken into account(momentum would matter here).  

It's physics. No matter how much mass an object has it will fall with the same acceleration as a heavier or lighter one. Take, for example, a rifle being fired parallel to the ground. If you drop say a rock at the exact same time that you fire the rifle both will hit the ground at the exact same time. Also if two different masses are shot at the same angle with the same velocities (assuming air resistance negligible) they will land at the same distance. So this leaves us with velocity and angle of shot to get distance.

My guess as to why the lam birch went further than expected is, for one, the shorter fletchings compared to others tested reducing drag, the angle of shot not being precise, and the heavier shaft's momentum helping to reduce effects of wind resistance on the fletchings/arrow. Also have to take into account arrow flight out of the bow with each arrow, arrow material paradox(tapered won't paradox as much), shaft material ability to recover quickly from paradox, and smoothness of release.  Lots of variables here.
All else being the same, exact same arrow with different mass- lighter one will go further due to increase in velocity. You'll never see a heavy arrow in a flight competition.

Nice looking bow by the way     Oh and thanks again for letting me borrow the video. Great stuff in there! Cheers, Matt

[Anvil]

Thanks guys! Good info. I also repeated the test with and without the Eagles Flight mini quiver, it did not effect things at all.
Matt, glad your enjoying the video. I look forward to doing some shooting when you get back to the States.

[Jason Jelinek]

My feeling is that even though the heavier arrows come out of the bow slower, the momentum is higher and drag has less of an effect.  The 2020 has a much higher FOC and probably had less osciallation (wiggling) when shot and reduced drag.

If you look at flight arrows they have very small fletching (for reduced drag) and are even barrel tapered (for reduced drag and lower FOC).  If lighter arrows had the same size fletchings (5") as the heavier arrows they probably wouldn't go as far because drag has a much more pronounced effect on the lighter arrows.

Jason.

[Kelly in Wisconsin]

Your 2020 is closer to the correct spine for your bow, hence cleaner and longer flight. 70-75# woods at 29" with 160 grain points are really only 60-65# spine. They may fly straight but are taking longer to correct from paradox than the stiffer, smaller diameter 2020 arrow. Would have liked to see a carbon amongst these to see how much farther it would have gone than the 2020.