Finally a fellow phD that I can listen and compare science. Your conclusions are so similar to mine. I believe that broadhead integrity post impact as it passes through also makes big difference. Another trade off is wound channel vs. penetration. One should consider the animal characteristics. Love it. Please do more. I’m so sick of listening to people that have no science background talk as if they do. Refreshing to have a science guy like you.
HAHA I'm not quite sure I qualify as a phD. However, I am trying to provide solid education on what does and does not have effects on the big topic of today in archery. Thanks for watching!!
I’m working on a solution for that. Currently building an app version of my archery ballistic calculator. It’ll be on IOS first then hopefully android after that.
With regard to column buckling on the front end of the arrow, in addition to adding FOC, adding a footer to increase the actual rigidity of the shaft seems to have a positive effect on penetration across all arrow weights.
Very, very fantastic video. Keep up the good work man! Start with the broadhead and work your way back. Decent FOC, appropriate spine and sharp broadheads will cure 98% off all problems in my opinion. Doing some more figuring here. If I was to add 100 grains from my similar setup from 483 to 583 I'd be gaining approximately 9% penetration from this analysis. While giving the animal up to 15% more opportunity to move. If it did elect to move, which they often do, It is just like a boxer soaking a punch & accelerating away from the arrow down and away. Which based on my calcs at 45 yds could easily rob around 12% of the KE & 5% of the Momentum because those vectors are no longer in the same direction. In addition to changing the impact location of the shot by the animal moving. So it seems to me the gain is really only tangible if the animal doesn't move. Which is a crap shoot but is the reality that we should plan for. If it doesn't move great, if not great. There are tangible downsides to faster arrows, the primary being they can be finicky with fixed broadheads. In theory they don't penetrate as well but that only is if the animal doesn't move. If you want to see some great examples of the downsides of heavy arrows in western hunting applications The Hunting Public is chock full of them. Love those guys but they're fully committed to the heavy arrows, albeit most of them have lightened up some. Ranch Fairy did a video stating that the "math doesn't work" for animal reaction. Lucas did an accurate one debunking that. They absolutely can move more. The whole "voting" thing is nonsensical as if it doesn't vote then awesome. We're not concerned about animals not moving... we're concerned about when they vote to. In this video Ted is shooting a 575 grain arrow with a sharp COC Magnus. Moving around 206 fps. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-8M8bBuAJcXE.htmlsi=tihfxWE8xKBnNxe7&t=586 9:55 at an antelope buck. Then again at 14:40 Then finally at 18:40 - notice how when that antelope turned it was just as I described as a boxer. Next to no penetration - even with a cut on contact broadhead and a heavy arrow. Another Ted video - "he was further than I thought he was". This was a painful recovery. I've been there and it sucks. But maybe a little more speed could have put that arrow even 1/2" higher and maybe 1/4" further forward (as he was walking) and led to an easier recovery. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-7sZAyQiGui8.htmlsi=DBBZiyzorJYLlzBp&t=760 I'd be interested for you to input Ashby specs at 650 grains and compare it to your setup. It has never made sense to me that a longbow at 650 grains would exceed the penetration ability of a compound like ours at say my 483 grains and 289 fps launch.
This is great stuff!!! I had to watch it twice to get everything. You pack a lot of info into 11 minutes. Not complaining! Can't wait til your next vids.
Great job and thank you for all the hard work. You make me think, how I can improve my setup to decrease my wound loss rate with better arrow performance. Thanks
Hey Lucas, thanks so much for the videos and all of the work you’ve put into this topic! I was talking with Kyle from trulineoutdoors and he said I should talk to you about another vane option to test, the firenock aerovane 2. I’ve got some and extra arrow shaft and I would love to build and send you a setup to run, just curious what you would need from me to test those out. Let me know!
Hey thanks for reaching out. I have some aero vanes 2 from a buddy of mine! However, another test fixture is always helpful! If you have a broken shaft those work perfect. The “arrow shaft” for the wind tunnel is about 7in long if you have a busted arrow with a good front end and wouldn’t mind fletching it up to test? I would appreciate that! Feel free to get my number from Kyle or reach out to me at lucaspalmer7@gmail.com.
Could you incorporate a Monte Carlo simulation to allow some of these variable to move within an acceptable range and then plot the results. You can then extract a tornado diagram grabbing the most significant variables within the simulation. This is some of the very best analysis of penetration I have ever seen. I have always known that measuring penetration into foam or ballistic gels are not representative of the real world.
how are you defining "high energy bow" is that: Draw Weight; Velocity as it leaves the bow; a Combination. bow configuration will effect velocity , draw weight MAY effect velocity Heavy Heads , Lite Shafts , fletching? depends on range to target now doesnt it
Energy of the bow is what energy it can deliver to an arrow at launch. Different arrow weights and launch velocity affect drag and therefore down range retained energy which is all accounted for in the calculations. Thank you for your question.
So my 463 grain arrow is shooting 323fps and my 500 grain arrow is shooting 310fps. They both come out at 105lb of kinetic energy. So heavier arrow will penetrate better even though it’s same kinetic energy?
From 450 to 500 is about 5% from 450 to 550 is about 9% from 450 to 600 is about 12% from 450 to 650 is about 16%. This assumes identical broadhead, shaft diameter, bow tune, dynamic spine of the shaft, shaft length, ect all being identical. Stiffer shafts can absorb more energy before deflection and thus perform better from a penetration standpoint. Which shaft diameter induces more resistance. Again thank you for the question!
Feet Per Second? If a 350 grain shoots 300fps then that same bow would shoot a 550 grain arrow it would slow down to 225fps so the penetration would decrease extremely
In the equation, you are looking at force. Not momentum. most say its momentum that gives us penetration. You are talking a lot about work. work is the change in kinetic energy. so which one is giving us the penetration? Thanks again.
In the real world you can’t use either. Targets are reactive to the forces applied I.e the great force you apply the great the force the target applies back on the projectile. Generally momentum is a better judge but that’s only true if the energy is the same for each projectile. If both energy and momentum are different for the projectile then you can’t use either to compare potential penetration amounts. The poncelet theory/equation accounts for this by looking at the specific forces and reaction force involved over intervals of either time based or distance based. So a mix of both energy and momentum are used in its analysis. So ideally force is really what matters reduce the amount of force applied by the arrow for penetration will reduce the reaction force. You primarily reduce needed force through broad-head design/sharpness and reducing impact velocity. But the direction you apply the force is a very important thing. Consider an arrow that hits sideways vs an arrow that hits square to target. The force of the untuned arrow is directed in the wrong direction leading to poor penetration or arrow redirect. Sorry I’m long winded.
@@Lucas_Palmer_bownerd_engineer@leap_outdoors The reason I asked is in animals, a heavy arrow with less KE but equal or slightly greater momentum will not out-penetrate a lighter arrow with a greater amount of energy. We see this with recurve vs compound bows. This is why I asked. Even in non-animal testing, using a hard impact test, a lighter arrow with a greater amount of energy will break the test media, whereas the heavy one with equal momentum will not. again thank you for your replies.
@@Lucas_Palmer_bownerd_engineer, I reread what you wrote: "Generally, momentum is a better judge, but that’s only true if the energy is the same for each projectile." I agree, but the question is, is it mass and momentum or mass and KE that gives the penetration? If we isolate momentum, we see its mass and KE. Sorry for the questions. I have been studying this for a while now, but I have never worked the Poncelet equations. This is very interesting to me. Thank you for taking the time to make the videos and break things down by looking at it through physics.
@@Lucas_Palmer_bownerd_engineer thank you again. im going to write down your equations and see if I can figure them out. Cannot wait to see the wind tunnel testing.
