How much momentum does an arrow lose at 60 yards l Ashby Bowhunting Foundation

Part 3 in a series on Long range arrow performance. Links to the first 2 videos below
Arrow Speed Erosion 0 and 60 yards: • Arrow Speed at Launch ...
Arrow Kinetic Energy 0 and 60 yards: • Kinetic energy loss in...
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Sirius RF Arrows and RF test Kit: siriusarchery....
Ranch Fairy Field Point Kits: siriusarchery....
Adult arrow binge list
1. Heavy Arrow Handload Video: • Bare shaft arrow tunin...
2. Bare Shaft Nock Tuning: • Bare Shaft Nock Tuning...
3. Fletched Nock Tuning: • Nock Tuning Fletched A...
4. Unpredictable Blood Trails: • Bloodtrails are NOT Pr...
5. How Broadheads Kill: • How Broadheads Kill
6. Broadhead Penetration Basics: • Broadhead Penetration ...

[@ApexPredatorOutdoors]

They are trying to strawman you by saying 700 or 900 grains all the time. I used to be a skeptic until I started listening. Then I subbed 2 years ago. Thanks Troy for always being authentic.

[@RanchFairy]

The straw man is on fire now

[@ApexPredatorOutdoors]

@@RanchFairy Good. Let it burn! The numbers don't lie! Everyone can make whatever choice they want, but 500 to 550 seems like a great ethical/speed balance for Johnny everyman... Do you agree?

[@RanchFairy]

@@ApexPredatorOutdoors Structural integrity Perfect arrow flight SHARP (learn this) Then yes

[@ApexPredatorOutdoors]

@@RanchFairy 💯%

[@darnellwatkins4031]

@@ApexPredatorOutdoors oh snap, two of my favorite archery channels together! I bought the zinger 2.0’s because of you! Well, and mainly Troy telling me to bare shaft tune and I needed to shave my fletchings Off! 🤣

[@scott5764]

Hell yeah, PHYSICS!!! Wish I had been bow hunting back in college could have done projects of my own. Amazing content and once again can’t argue with results.

[@MrAPCProductions]

The easiest way the bone breaking of either a bullet or an arrow has been explained to me is the example of what you use to cut firewood. You can swing a hatchet extremely fast, but cannot carry enough load to rupture the connecting tissue of the wood. Opposite end of the spectrum is a 12lb maul that carries all of its weight through the wood.

[@MrAPCProductions]

Side notes: I have personal experience seeing several Class 2 game hits with 400-465 grain launched at or near 280fps. Enough to break ribs, but never legs/shoulders Have seen two shots from last year from a nearby hunter who started me down this RF path. 715 grain at 205fps, broke both legs, a few ribs, cut the shoulder to hell and went 12-16 inches into the dirt on the opposite side. Second shot was similar results but instead of dirt stuck in a tree 5-6 yards behind the second buck. I can't tell you what the magic energy number is, but I can tell you that of all of the animals I've seen taken over the course of my life, no one has ever questioned the efficiency of a 12 gauge slug.

[@wiscofun3028]

First off I think you mean split firewood, not cut it, but I digress. The maul has 8 times the mass of the hatchet. Too make that analogy work you'd have to compare a 350 gain arrow to one with a mass of 2,800 grains. As you can see the analogy is ridiculous. Would you rather split logs with a hatchet or a slightly bigger hatchet? Neither.

[@RanchFairy]

@@wiscofun3028 Hang on there wisco. More coming on that. Bones can easily be broken but the arrow has to have a set of factors. We’d prefer to NOT hit heavy bone. But plan B does come a calling sometimes. Plan B arrows work in plan a. The reverse is not true.

[@WM-jy9dz]

@@wiscofun3028 ...and you wouldn't use a heavy ax where the blade has a shape that gives it a MA of 3 (like an "adult" BH) either....so yes, the analogy is somehow flawed....well, not totally as it might lead to considerations that the current promoted "adult" BH with a MA of 3 or higher is not perfect when hitting bones...

[@MrAPCProductions]

@@wiscofun3028 you don't shoot 2800 grain arrows for fun? Try its a riot. 2219 shafts with stainless rod through the center, 300 grain insert, and a 600 grain field point. I have no idea what the real weight is, but on my food scale its 7.5 ounces.

[@powderhogg01]

love it. stuck a muley this year. using a higher grain high foc. deer didnt even react to the shot. just stood there and tipped over, rolled right to me

[@bobtosi9346]

That is a good ethical death for an animal. Good for you on your success

[@powderhogg01]

@@bobtosi9346 because of how thick it is here, i rarely get to see em drop. even if they only go 30, so it was a rush for sure

[@Atheos119]

its crazy to me how these videos only have 7-8-10k views. When you go to ANYONE and talk about archery now, they've heard of the ranch fairy. My uncles, cousins, my local bow shop, everyone knows now. This channel IS changing things keep it up.

[@Bryan-vz4sz]

Whats funny is all the people who drag you through the mud with the bullshit 800 grain arrow talk STILL end up saying exactly what you say. THey just phrase it as "a happy medium" which seems to always entail a 500-550+ grain arrow with high FOC etc etc.. Thanks for your content.

[@AndrewLakey]

I believe you are on the right track in regards to a momentum value vs just a stated mass of a 650gr arrow is the bone breaking threshold. Stating the obvious, way too many variables with just stating a grain weight....but a momentum value is achievable in various ways by combining velocity AND mass. Keep up the good work (from a nerdy engineer)

[@AndrewLakey]

@ranchfairy Troy, It has to do with inertia which needs to be part of the discussion. Momentum is how much energy an object has and in what direction it is moving. Inertia is an objects resistance to change it's motion....or in this case the resistance to slow down upon impact. You can get high momentum numbers by increasing velocity or mass...you increase inertia by increasing mass. Below is a simple comparison between Inertia and Momentum that I think may help...keeping the discussion regarding arrow mass and velocity it looks like this. Arrow small mass and small velocity = Small Inertia and Small Momentum Arrow with small mass and large velocity = Small Inertia and Larger momentum Arrow with large mass and small velocity = Larger Inertia and Smaller Momentum Arrow with large mass and large velocity = Large Inertia and Large Momentum KE is like a snapshot it time...like looking at your speedometer in your truck and seeing you are going 60mph...it doesn't have a vector(direction) because of you square the velocity in the KE equation you greatly increase the value by increasing the velocity. It is a very poor way to determine how an object reacts in collision because Momentum is the only force conserved in a collision...but KE does sell bows. I think they are on the correct path in determining a "momentum factor" or something to that effect. All good discussion.

[@RanchFairy]

@@AndrewLakey Www.Ashbybowhunting.com Ashby reports

[@v.n.6886]

@@RanchFairy somewhat deletes hints, that this link is wrong (if I include the right link). this link leads me to a domain seller btw I've just read the report you mentioned and have to say that the Silver Flame BH is no unicorn. you can still buy it (at least here in Germany)

[@RanchFairy]

@@v.n.6886 www.ashbybowhunting.org/ashby-reports

[@AndrewLakey]

@@RanchFairy All great references, I have read the reports several times. in my humble opinion, there isn't enough discussion regarding inertia and how it applies to the results you are seeing with the empirical data. Inertia describes how a mass resists motion(or in this case resists a change in motion...resists slowing down) It can easily be used to describe why if you have two arrows with similar momentum that the more massive arrow will perform better on bone, sheds velocity, momentum at a slower rate, and out pernitrate the lighter mass arrow. I remember the little Dik Dik bow with a very heavy setup lobbing arrows through stuff...inertia. You described a "momentum factor" for reliably penetrating and breaking bone but you might want to consider an "Inertia factor" or have it in the discussion. Keep up the good work!

[@davidcerone3998]

All I can say is I followed the instructions you gave and at 653.7 grains exact and with a magnus buzzcut 4 blade at 70+ yards my setup will knock down freezer queen doe and big buck alike with less than 10 yards of post shot travel

[@RobertKearl-Outdoor-Adventures]

I'm glad I found the Dr Ashby's 12 steps and your channel , I've always been a light fast flipper flapper twizzler stick arrow kind guy till I decided to go heavy 682 grains off an 80lb bow chronographed at 249 fps at 6 feet sight taped at 233 fps

[@toddgreenlee9406]

Great content. I changed my entire setup last year. I did that after learning from your channel. 32 inch draw 80 lbs draw weight 720 grain arrow weight.

[@kz1000guy1]

You shooting a bow or a cannon? 😅🤣 damn that must hit hard. I found Ashby first, and ranch fairy later.. its great to see someone given the work new life.

[@JedlyMT]

I changed this year too. Painfully though. Learned a lot. No matter where you add weight(draw weight or arrow weight), add a stiffer arrow. Learned that the hard way trying to shoot a 320 spined arrow with 200 grains(broadhead only) up front. Finally went to a 250 spine arrow. Really hoping I get a chance to hit something with a 666 grain arrow with 16% foc.

[@justinsalzl1517]

@@JedlyMT you’ll love it when you do! I shot a Sirius Apollo 250 last year. 30” draw, 72 pounds, 740 grain arrow. Doe at 31 yards, hard quartering to. I heard the pop as it passed thru her. Almost full length of body pass thru, arrow went 8 yards past her and buried over a foot in the dirt. The Tuffhead Meathead 265 is nasty!

[@richarddean3154]

You make your best case when you compare the 516 grain arrow to the 389 & 436 grain arrows at launch and 60 yards. 516 grains is achievable by many archers, while still using 100-125 grain broadheads and can better survive PLAN B scenarios. Keep working on the masses and they will eventually come around. Thanks for the great video and explanation.

[@jakeoubre3929]

Hey man love what u do changed my point of view big time. Also i think its hilarious how all the big time sponsored tv hunters take offense to it. Your making them sweat big time haha

[@A15Dude]

Momentum as a measurement of penetration potential is absent in the world of ballistics. I’ve been playing with bullets for a long time and all any of us ever thought about was trajectory and KE. Trajectory tells you only how sloppy your range estimation can be, and KE tells you how much energy the projectile is carrying. KE remains the same for a given weight at a given speed, but it’s no guarantee of what really matters and that’s terminal performance. Dr. Ashby proved it over and over again that a purpose built projectile that stays intact will penetrate best because of momentum, KE notwithstanding. This is why a Barnes-type bullet that sheds no weight always penetrates better than a bullet of equal launch weight that comes apart while flying through flesh and bone. Why I never thought to apply what I knew about terminal ballistics to an arrow is something I have no excuse for, but those days are over! Thanks for the outstanding work you and the Ashby Foundation continue to do!

[@big_ol_ben4152]

I did email you Troy but I'm saying it here as well. I sought your advice two winters ago. Your advice was spot on. 800 plus grains on a 300 spine. The arrow found its home on a mature bull elk today. This guy is the real deal.

[@mikemarion4799]

How about a video that shows momentum/KE compared to the trajectory difference of those different weight arrows? This would provide the heaviest arrow for acceptable trajectory data like Ed Ashby promotes. Also curious if you've done any radar speed testing with broadheads on the arrow to see what/if any additional drag is created.

[@tylersuchy672]

Just got out of my college class, learn more here then the indoctrination labs at school

[@RanchFairy]

Ha

[@guitarq359]

The elk argument is my favorite. “I need a light arrow to hit the animal at 60 yards, but I’m going to ignore the fact that it may not have enough momentum for lethal penetration.”

[@RanchFairy]

Fact “of course it’s gonna penetrate, it hit the animal”

[@royleerobinson5]

Is .734 slug at the bow over kill? It’s going 250fps so it’s not slow. I’m going to work out to distance. I just got them put together and shot them in the garage on paper. They shot like darts! This is a elk set up fyi 675gn total weight

[@jons7e]

The best combo is a large power source with a heavy, structurally sound, projectile. It's just common sense. What gets more complicated is when you have a small power source, as it will limit your effective range, and that's where compromise will be apparent. But for most men shooting that 65+# bow, there's no reason not to experiment if nothing else.

[@flushot6513]

Funny how you see those guys on hunting channel shoot whitetail and have over half the arrow sticking out of deer shooting high poundage bows

[@andre1022c4]

I was wondering, since Dr. Ashby's 650gr bone breaking arrow was shot from a stick bow if I remember correctly: my hypothesis is I think that momentum value is going to yield us a number in the 0.55 to 0.58 considering that he was probably shooting a 650gr arrow at velocity of 150-180fps. It would stand to reason that with our faster more efficient compounds you have incredible success with arrows now in the 500s as you mentioned do your best to get to 550, loaded in the front with perfect arrow flight and structural integrity.

[@ThatJamesGuy88]

Epiphany moment-arrow effectiveness depends on arrow momentum overcoming target resistance, while cutting vital tissues. The argument about kinetic energy is moot-arrow effectiveness is reduced be the amount of energy transferred to the target. Bow hunters don’t kill animals with kinetic energy, they kill by using a sharp stick to cut vital tissues. Or maybe I’m just dumb and everyone else already figured this out. Either way, keep up the good work.

[@livingadreamlife1428]

Sure, as long as it’s a perfect shot. Where momentum and KE come into play is with a shot that is off-center and not in the vital V. Instead, when it’s at the front shoulder or other bone mass location, momentum and KE come into play. So, i think you agree, there is more “shot forgiveness” with a heavier arrow because of those factors.

[@ThatJamesGuy88]

@@livingadreamlife1428 I’ll disagree specifically regarding kinetic energy in the context of causing a lethal injury to an animal. If you strike a bone or other non-vital tissues, you want to transfer the least amount of kinetic energy possible. That’s where Ashby’s factors come into play. Higher mass, perfect flight, high integrity, 3 to 1 ratio, etc. If the arrow transfers kinetic energy to the animal, it will lose momentum and penetration will suffer. But I think we want our arrows to penetrate and cut vital tissues while shedding the least kinetic energy possible. Maybe this becomes a discussion about efficiency? (I’m not a rocket scientist, so my verbiage could be wrong. 🤷‍♂️)

[@jake4194]

This is excellent, I myself always wind up thinking of arrow energy in fps and ft lbs, but your right arrows need momentum to retain their ability to cut through a target, not dump it all to create hydrostatic shock or something!

[@Bigdancustomknives]

Awesome content please keep them coming. I’ve learned a great amount from watching your videos and doing my own testing/research. I don’t have a lab radar but im curious about the change in momentum from the change in FOC. Keeping the mass as constant as possible while moving the foc up and down

[@hall0341]

I would like to see the momentum calculated from that 650 grain arrow that Ed determined was bone breaking.

[@RanchFairy]

The chart is CLEARLY there He was going slower

[@hall0341]

I did not clearly state what I was curious to see. I would like to know the momentum that Ed was achieving with his bow and the 650 grain arrows he determined to be bone braking. Of course, momentum is not the end all be all measurment for penetration as the same momentum can be achieved with two different arrow weights, but the slower arrow will penetrate better. I was just generally curious on his numbers and haven't seen it in the reports I have read.

[@stevenperue1528]

I've been slowly tinkering with my bow and have a great setup now that's shooting great. made the jump to a single bevel grizzly stick Samaria 200g from a 150 g magnus stinger. wasn't expecting so much improvement. but im shooting a 200 spine serius appollo with lighted knocks 100grain half out and a 200 grain single bevel. my bow is a mathews monster chill r with a 31 in draw length and a 75lb draw weight. the KE at launch is somewhere in the 92ftlb range and about 245ft/sec and my arrow at 30 yards blows through both of my targets. had to refletch a few arrows. now I know that my broad heads fly good. needless to say I won't be shooting them very much for practice because I can't afford to loose them lol. Oh yeah my overall arrow weight is 783 grains

[@aaronward3882]

Remove the half out from your system. Half outs are notorious for failing

[@davehalm7362]

Thank you for continuing to share the truth about heavy arrows. You're catching a lot of heat from other folks.....ya know....the self proclaimed Professional bowhunters on TV. I was really surprised sell out Wadell had some negative things to say about you. Guess Walmart won't carry Adult Arrows so he can't get paid. I really think those guys are just late to the party and don't have the balls to admit when they're wrong. Again, thanks for making sense.

[@RanchFairy]

Thank you.

[@robbourn7379]

Watched a video of Cry Baby Waddy shooting his flappers that BOUNCED OFF A BUCK shot behind the shoulder ! Amazing that they keep promoting disposable heads.

[@davehalm7362]

Yea, I don't understand why either. Like ole RF says...why not eliminate all the variables and go heavy 🤷‍♂️

[@drewsroo]

How many Drury videos have you watched where you hear "I can't shoot him there he's quartering to". Wouldn't it be neat if there was a way to eliminate that variable?

[@WM-jy9dz]

​@@davehalm7362 one variable for a lot of hunters is actually distance - not everyone shoots always from the same tree stand in close vicinity to a feeder, and increasing distances and increasing weight will increase the time the arrow needs to the target, and the game might not always sit and wait till it gets hit by the arrow....

[@jolookstothestars6358]

Thanks R.F. for making more magic! ; )

[@flounderwetspot8524]

Are you going to do a summary video of speed erosion, ke, and momentum ? Just some take always all combined in one video ? I’m at 619gr and loving it for out to 35 yards. Poor block target doesn’t appreciate it much though haha

[@toddferrell518]

Just for giggles the pro shop that ask me if I was watching that ranch fairy dude posted his 550 grain arrows on Facebook today 😂😂😂

[@DomT0311]

There's so much money to be made by bow shops if they take the time to learn heavy, high FOC arrow set ups and then charge people to set up their arrows, but they're too ignorant to do it.

[@Hubble-M]

If your savvy with automotive power, you can explain it comparing horsepower, torque and engine rpm. I've been closely watching your content since It. Keep up the good work sir, im going to use your math for a build and see if I can take some additional measurements for two or three other guys and their systems and see if there is even more to it.

[@RanchFairy]

Great advice and working on that

[@eddiealvarez5493]

Excellent job RF! You the Man.👊

[@Bowhunter1300]

These videos are fantastic! As far as I can tell, you folks at the Ashby Foundation are the only ones doing actual research on this subject.

[@WM-jy9dz]

First: I agree with all the data presented in the video - fully plausible and just representing the mighty physics 👍. Second: I don't agree fully with the conclusion that momentum equals automatically penetration - here the logic to this: I think the following is something even Ashby struggled to get his mind around. Most of the time we overlook that tissue has some kind of flexibility and elasticity. Every time I'm cutting lung for the dog I'm just puzzled how genius mother nature designed this kind of tissue to avoid being cut. It is just so flexible and elastic that it wraps around an even sharp knife and needs quite some force to get cut. There are 2 ways to overcome this: I can slightly freeze it to make it less flexible (works), the second option would be higher speed (hard do to with a knife without cutting the fingers off 😁). Why does higher speed works? ...because of the own inertia of the lung tissue. Elasticity can only work if there is time to move - no time for movement --> no movement at all --> no elasticity. If I minimize the time for elastic tissue to move, cutting becomes much more efficient as e.g. the lung tissue has less time to wrap around my blade thus minimizing the cutting stress due to a larger cutting surface. Therefore, when dealing with elastic matter, momentum doesn't help much, but speed does. (Think about cutting steel with water - it's all about the speed!!!). When shooting an arrow into game, most of the organic matter flexes - the more it flexes before the actual cut, the more energy we lose for stretching the tissue till it breaks - this energy is gone, we can't recover it. The momentum won't help to avoid this flexing and energy losses - speed does as the own inertia of the tissue works here in our favor. The faster the projectile (whether it is a bullet or an arrow), the less chance / time the tissue has to flex, therefore the better the available KE can be used increasing efficiency. Conversely, momentum would just help to stretch more tissue further thus becoming more and more inefficient (try to cut thick lung tissue very slowly without additional slicing movement!). IMO the physics and kinetics of an arrow FLIGHT from the bow to the game / target is pretty much covered, relative easy to predict and relative easy to back up by testing. The big challenge out there is - IMO - what happens AFTER the arrow hit the game, and that is a total different animal. Despite all my internet research I couldn't find any source that revealed data for speed (when we measure the speed we can always calculate the momentum and the KE for a given arrow weight) BEFORE AND AFTER penetrating through a game or specific tissue thus revealing the efficiency of various arrow setups. And exactly this is required to find the optimal combination of speed and momentum for the most lethal arrow.

[@drewsroo]

I like your mind and the way you think and the questions you ask. My question for you is, do we need to do testing on what degree of sharpness will cut through elastic tissue better, does it matter how sharp the head is. Because sharpness is certainly something that can be measured and applied to this whole equation now.

[@WM-jy9dz]

@@drewsroo try to cut lung tissue with a blunt knife 😁 - compared to bullets arrows are relatively slow, but having also a relative big cross section: without a sharp broadhead there is a) no chance of good penetration for bigger animals, and b) less chances for cutting enough veins for a fast kill (for small game, rabbits etc. id doesn't matter - here a blunt tip / small game BH is an advantage as it kills the animal fast just on impact with a compound bow - 30# and higher). The test setup I have in mind is a box with defined WxHxD, filled with lung tissue; to prevent it from falling out I could use some lightweight foil. Then measuring the launch speed of various arrow setups (just shooting in a foam target). Then I have to place the chrono behind the test box and shoot through the tissue and the chrono. Happens all in close range so any air friction losses are neglectable. Now I have the speeds before and after and can calculated the KE losses in the lung tissue for a defined penetration depth. Of course, the meaningfulness of the results are still debatable as there are just too many variables in the real world to cover: bones, density of different tissues, living tissue vs dead tissue etc. ...nevertheless I think it would be a good start for gathering some valuable data. And to get back to your question: all BH need to be as sharp as possible to minimize the impact of this specific parameter.

[@jake4194]

150mph is by no means slow and going to stretch the tissue, thats about what the heavyweight arrows are doing. Light ones closer to 190 mph.

[@WM-jy9dz]

that's an interesting one: kzbin.info/www/bejne/q2elfYtpr9F9oc0&ab_channel=TuffheadBroadheads ... the single baffle does "more damage" as the flexible tissue wraps around ...while the video demonstrates the bigger damage in flexible tissue, unfortunately it doesn't give any information about the KE that is consumed for this damage. My understanding is that this pulling of tissue comes at the price of higher KE consumption (the force for pulling tissue has to feed on something). ...so single baffle --> more damage in flexible tissue, but likely less penetration - would be similar to a mechanical vs. fixed BH cut: the higher damage always comes at the price of less penetration.

[@FlyinZX10R]

I’m new to archery. This was very informative. Thanks :)

[@RanchFairy]

here to help ya. lots of info here. Welcome to the crazy train.

[@markbarefield7570]

Good stuff… as usual. Ready for the high speed stuff.

[@seantnper881]

I would love to see this done with a lever bow. Like an Oneida Phoenix. I think the results would be interesting since everything I read and hear… lever bows shoot heavy arrows the best.

[@niklassvensson9119]

Would be the same thing. An 500 grain arrow launched at 250 fps from one bow will have the same momentum ect as another 500 grain arrow launched at 250 fps from another bow. Physics dont care about brands (or feelings).

[@paulpurpura191]

Greetings from Nelson County, Virginia. I just wanted to tell you how much I enjoy watching your videos. I have learned much from doing such. I hold a bachelors and a masters degree in engineering and because of that I really enjoy listening to Dr. Ashby. I love the technical side of the sport, especially arrows in flight. I also like listening to you too Ranch Fairy. You present your funny side in your videos, but you ain’t no dummy. Keep up the great work!

[@MrJNOTHUM]

Read the Cape Buffalo case study...wow. 39# bow with superior head did better that the 82# bow with 1100+ gr. total weight with a lesser head. Insane!

[@WM-jy9dz]

the poor performance of the bishop (same shape, form factor and weight) than the other "adult" arrows with FPT seems very odd to me ...when reading through the narratives it seems that the arrow with this head wasn't tuned properly...an UFOC around 30% would make this tuning also much more challenging thus increasing the likelihood of a bad tuned arrow.

[@RolllTide]

Seems like the magic number would be 0.60slug ft/S or above. Keep up the good work Troy. Listening to your studies gets me home & out the woods a lot earlier then in the light/fast days. Now, if you could please make a video showing some tips or tricks for getting our arrows & broadhead out of the buried roots without breaking them.

[@andrewmccann7572]

Ok, this is great stuff, but the next test should be to measure the flinch of an animal, and see what speed you really need to make an ethical shot at 30 yards, 60 yards etc.

[@sethwinkel5721]

Growing deer tv, had/has a good video on deer reaction time and arrow speeds,

[@WM-jy9dz]

.....something from another "test lab" kzbin.info/www/bejne/f4i7iIh4jLimsM0&ab_channel=GrowingDeer.tv ...

[@timl8302]

Hey Troy!! Seriously, look at graph shift at 589grain arrow. Interesting?!

[@drewsroo]

Just finished building my first true "heavy" build this evening. 95 grain Ethics insert/outsert, 150 grain Stinger for a grand total of 570 with 18.5 FOC. Would have gone heavier but with the arrows I have I am on the brittle edge of being underspined. They shoot like darts and are grouping great. My target isn't going to last long however.

[@jake4194]

That sounds like a pretty good weight. About what I would choose!

[@baraksinz]

Momentum is simply the ability of an object to continue moving when it encounters resistance.

[@maplehappy]

fantastic video and info as always RF! hey has anyone ever told you that you kinda look like james hetfield? yall could be brothers lmao

[@HoneyBeagle]

Exactly why you don’t generally shoot elk with 90 grain bullets. I’m somewhat new to archery hunting but have been overly obsessed with rifle hunting, shooting, load development , and gunsmithing for several decades now. Heavy bullets may start out slower but they carry much more energy, momentum, and penetration down range. Actually at a certain range a heavy for caliber bullet will pass a light offering in velocity as well due to efficiency. I wonder if there is a point where an arrow would be behave in the same manner.

[@tyrander1652]

Do you have any numbers (or consolidated/combined numbers) on bow draw weight vs arrow weight, and bow noise vs fletching noise on string jump. Is it possible to tune a system so the noise volume or sound frequency won't startle the animal? Also, animal eyes are more tuned to movement than ours and their conscious reflexes are much faster than ours. Do you have any thoughts on them detecting sharp movement from the bow as well as hearing sound? Probably more for deer than pigs.

[@16912outdoors]

You are right about this. Maybe the people who shoot ballistic gel should test shoot at 60 yards their light twizler stick to a 650gr set up

[@african7498]

You call it good old physics - irrefutable. The more resistance a target offers (tougher, bigger) the more momentum is required - the more force that needs to be overcome - the more momentum is required.

[@HickLif3]

Just thought I'd say that I really enjoyed your talk with Aron Snyder on the Kifaru cast. I knew yall would have a lot more in common than he thought. Especially the way he had been talking on Elk Shape and such. I think it will help clear the air for some that just look at the surface level and see where you really stand on things. Also I wonder at what point is there diminishing returns or where is starts to flat line for the momentum. It has to be up there at a completely unrealistic arrow weight like 1500 grains or something

[@RanchFairy]

Depends on what you’re hunting 1200 is relatively normal - for elephants and hippo. 650 is still the only scientifically established bone breaking threshold. But - pure physics - the mass wins On meat and inertia Delivering it - different story.

[@HickLif3]

@@RanchFairy i was thinking from a pure physics stand point. Basically take the weight of the arrow up until you reach a point that the momentum peaks and starts to decrease for a specific bow. Basically saying that would be the max weight you would want to shoot for that specific bow because you lose momentum once you go past that.

[@RanchFairy]

@@HickLif3 Not sure that happens. Well if it doesn’t launch!!!! Ha! The equation is mass x velocity.

[@WM-jy9dz]

​@@HickLif3 it depends on the height of the arrow to the target and the KE your bow develops pending on the draw length and poundage. .... let's say we still want to hit a rabbit that is 3 meters away from us sitting on the ground approx. 1.5 meters below the arrow rest. To move the arrow 1.5 m to the ground via free fall the arrow needs 0.55 sec (based on the equation DISTANCE = 0.5 x GRAVITY C. x TIMES^2 ).That means the arrow needs a speed that allows it to reach the rabbit before it drops to the ground, hence it has to get to the 3 meter mark in 0.55 sec. Thus the speed needs to be approx. 5.5 m/s (that's approx. 18 fps). So for my draw length (31") and poundage (64# for training) my bow gives me a KE of 113 Nm (I stick now with SI units as I live in a metric world and it's easier for me...) ...so I know my KE, I know the speed (5.5 m/s) hence I can calculate the max. mass of the arrow based on the equation KE = 0.5 MASS x SPEED^2 which gives me: 2.7 kg ....that are whopping 41,667 grains .... So there would be some room for making my arrows (430 grain at the moment) a "little" bit heavier and more lethal for this little rabbit 😂😂😂 Now if you stand on a 5 meter high tower... Eta: ...just make sure that you are wearing safety boots in case the arrow drops from the rest 🤣🤣🤣

[@suthernmutt1459]

i noticed the videos that reference heavy arrows talk about he trajectory of the arrow and they dont want to be arching to ge tto the target. do you plan on showing the arrow trajectory comparisons? i would find that to be a fun video to watch. and i woul do it my self but i have only been doing archery for almost 2 years and never gone to do anything past 35 yards.

[@RanchFairy]

I don’t know if this matters much. My focus is plan B hammer arrows that penetrate. The trajectory argument assumes the arrow will penetrate. One of the issues with 3-d archery. Makes you feel like hitting it - will kill it. Me and Rocketman will consider this idea

[@suthernmutt1459]

@@RanchFairy it hink their main concern is being in brush or a blind and you only have a limited amount of space for the arrow to fly unimpeded. even if this i snot their concern i still think it would be a good video for science purposes.

[@awesum0]

just in the woods in general, have to pay attention for broken branches hanging limbs anything where that trajectory could rise further than normally anticipated, but I think that is more something to train for and be aware of probably more than anything.

[@RanchFairy]

@@awesum0 Great comment I always wonder how every branch prowl talk about is always up? Hahahah No matter what arrow we run Practice in realistic situations Not on a golf course!!

[@justinsalzl1517]

My friends who disagree with heavy arrows come back to this point a lot. They want to use one pin out to 35 yards. Sight in at 27. A little high at 20, a little low at 35. But a dead deer. I know I couldn’t do that with my 740 grain setup. I just have to know my ranges better. At the same time, I haven’t shot past 31 yards. And it’s pretty easy to remember landmarks that are at 30 or 20 and in. I’ve ran my own unscientific tests, shooting arrows of different weights at 30 yards with my 20 pin and seeing the difference. The heavy arrow ends up being 2 or 3 inches lower than the lighter arrow. Arrows were about 540 and 630 grains. @ranchfairy, do you (or anyone) have any data related to this? Thanks again for all the hard work educating us! We truly appreciate it.

[@aliboo330]

I like to think of it as if a Kenworth was hitting a brick wall @ 60 mph or a Kia Soul 🤣

[@chuckdean260]

FOC fear of change.

[@SpearsUnclaimed]

I want to see a static 650 grain arrow shot at various speeds and record the momentum changes. That might unveil the 650 grain momentum curve that Ashby observed in his tests.

[@WM-jy9dz]

the momentum is just speed x mass ...so the changes are just linear changes proportional to the rate the speed goes up - why would you need to test this? ....if you meant to do this for various distances: Troy did exactly this already ...?....

[@enduroskillstraining]

Yup :)

[@Anthony-fk2zu]

“Would ya rather get hit with a bowling ball or a BB?”

[@ppoutside6723]

You look weird in a hat without the top half missing

[@vidsoutmike]

KE is a messenger. Momentum is the massage. HeHe >------->

[@saulgood6190]

Is there another way to quantify slug feet per second? A change of .2 might be alot in the field but on paper it doesn't represent a worthy change very well for most people.

[@JedlyMT]

I was wondering this. So my 666 grain arrow has nearly twice as much slug feet per second than most hunters lightweight arrows. What does that mean?!

[@WM-jy9dz]

@@JedlyMT ...it means that if your slower arrow might need ages till it reaches the game the game might have moved in the meanwhile and you miss it totally, but you will still get good mud penetration 😀

[@justinsalzl1517]

@@WM-jy9dz I ran comparisons, even giving the slower arrow the advantage by not including speed erosion at a higher rate over distance, and just taking the initial velocity. At 40 yards, out of a Mathews flagship setup, shooting a 425 grain arrow and a 600 grain arrow, the “heavy” arrow gets there less than a tenth of a second slower than the lighter arrow. It’s actually less than .075 seconds slower. And remember, the lighter arrow loses speed faster than the heavier arrow. So it’s even closer. And not to mention, deer tend to jump at the sound of the bow, and light arrows make more sound than heavy arrows. You will never outshoot the speed of sound with a bow no matter how much you try. So maybe instead of getting more mud, we don’t take the 60 yard shot that you will with a light arrow. But the odds of us wounding one without a shot are 0, and yours are slightly higher than 0. We’re not telling you how to shoot. So please, either stop looking down your nose at people you want to think you’re better than, and join the discussion like an adult trying to learn and improve, or just go away. Nobody here is interested in listening to you trying to stir the pot. Maybe try the calculations on your own if you really want to learn something. Good luck.

[@WM-jy9dz]

@@justinsalzl1517 Thanks for your comment - I'm here to learn, won't take long and I will be smart as you are.....here something I posted in Troy's video about helical fletching: ...lighter arrow was still approx. 40 fps faster at 50 yard than the heavier arrow... e.g. for the first fletch configuration the lighter arrow reached the target after approx. 0.52 sec while the heavier arrow needed approx. 0.63 sec....sounds not like a big difference? ...well, if we give a deer a response time of 0.2 sec it could have dropped 0.5 m for the lighter arrow, but 0.9 m for the much slower heavier arrow! So fact is also that the margin of error for the heavier arrow is nearly double as high (at 50 yards) - increased by a whopping 0.4 m!!! - compared to the lighter arrow. The response time of a deer to a visual trigger can be as short as 0.015 sec, for a noise trigger it is a little bit longer - the 0.2 sec I assumed is not the worst case scenario, but gives a good idea about the order of the potential error margin. Once the deer starts reacting / dropping it is all about physics: the dropping is a "free fall" due to gravity, and the travelled distance to the ground can be calculated by the equation "TRAVELLED DISTANCE = 0.5 x GRAVITY x TIME^2". (Wrt my calcs above you would take the response time from the time the particular arrow needs to reach the target at 50 yd). ...and here something from another "test lab" kzbin.info/www/bejne/f4i7iIh4jLimsM0&ab_channel=GrowingDeer.tv ...

[@mikeredmond2739]

@@WM-jy9dz on a video shot at 60 frames per second, the 0.11 second difference between those arrows equals just under 7 frames. You should be able to watch a deer drop/react to an arrow on a youtube video and count the frames. My bet is that it's an insignificant amount of movement, but I'll check in a bit.

[@richarddean3154]

You and the Rocket Man need to come up with a uniform medium that can act as a barrier to penetration and be used to confirm the bone-breaking threshold. Some high-speed camera work could show how lighter set ups wither under the test. Good luck

[@RanchFairy]

Ashby reports man

[@Bouboukenka]

Momentum=transferable inertia

[@bosullivan1433]

I agree with the statements made in the video, but momentum is a curve. At some point, depending upon mass and velocity, momentum begins to decrease based upon velocity drop due to mass. For a modern bow at ~70lb draw weight that starts to happen around the 620-670 grain data point (kudos to Dr, Ashby). Your video does not show that decrease, and could lead some to believe that momentum is ever increasing based upon your chart, but that clearly isn't true since momentum is simply mass times velocity. With that said, Dr. Ashby also said that an arrow that derives the majority of its momentum from mass instead of velocity will penetrate better. In other words, if both arrows have a momentum of 0.6071, but one is 805 grains moving at 170 FPS and the other is 510 grains moving at 268 FPS, the 805 should penetrate better. This is a study I performed with my Mathews V3X 29 at a 29 inch draw pulling 72.1 lbs. The point of this comment is to simply recognize that heavy is always better...to a point. For instance, the aforementioned bow produces 0.6344 ft/lbs sec with a 600 grain arrow and only 0.6071 with an 805 grain arrow, with a dramatic speed and trajectory issue of losing 68 FPS, the archer should obviously choose the 600 grain arrow. Long story short, folks should do the math to maximize the lethality of their individual setup. It is definitely not a one size fits all. Love the video though, keep up the good work!

[@RanchFairy]

Ok - but I stayed within normal arrow mass for achievable builds. If you’re right (I don’t know either way) You are sure welcome to help us find that point where “at some point” this happens. Ashby foundation can use all the help we can get.

[@F15Bluto]

I think I’ve finally digested this three part series. Tough to argue with science. My question is the application, not sure if it’s objective or subjective. What momentum “threshold” is acceptable? Better put (maybe?) would be, what’s the relative difference in the momentum measurement? Is there any appreciable difference in 0.04 slug ft/s? Still trying to balance longer range trajectory complications. (My whitetail setup is a no brainer. 250 spine Apollo’s at 600 or so gr.)

[@RanchFairy]

That’s a great question Somebody has to figure out the drag coefficient of each animals impact thorax. Then we could calculate a delta. At this time - given we have a VERY VERY low energy system 5-10% is a big deal And then there’s how efficient the broadhead platform works. And then….why in the hell don’t people who want faster everything And more horsepower and bigger guns Not want a bigger energy arrow. Nah - we want a one sided thong arrow!! Hahahahhaha

[@TheWVgoodguy22]

Science is fun. The other videos including the ones with The Hunting Public have been even more eye opening. I also recently listened to the podcasts with Aron Snyder and Kifaru Cast as well as the Vortex Nation Podcast. I enjoyed them all and unlike many I take everything in instead of just picking out words that I want to hear. My current setup is around 520 with lighted nocks, but I think I will change the weight distribution around next year.

[@officerfoxtrot3633]

I just changed my setup this year too but I’ve been on the fence for a couple years now about RF’s advice. I always agreed heavier/high FOC was better, but I was hesitant to take the serious plunge. If this arrow performance this year isn’t what I hope, next year I will go further Ashby. Mine this year is 29”@70#’s, approximately 250 fps. Running a Day Six 300 with 250 up front, 630 total weight, 14.8% FOC. Iron Will Wide and Magnus Killer Bee heads. If this doesn’t perform up to par, Next year I’ll switch to Bishop 315 Single Bevel, tuffhead 300 Classics with Ethics Glue In adapters, etc. I’ll run Sirius Orion Micro’s at 250 spine or 200 Spine, have a total weight of either 656 or 706 with 22.4% or 24.2% FOC. They’ll be flying 240-220 fps-ish. The Bishops are a hard pill to swallow. Currently they are running $400 for 3 of their 315 grain heads, but they should last forever. Mix in some tuff heads, maybe even 350 Valkyrie JagerBombs, grizStik Ashby 315’s, VPA 3 Blade 300’s, and some Iron Will 200’s with increased insert weight. Hell, I’ll probably add some heavy glue in inserts to 165 grain Simmons Tree Sharks and throw some 2” fixed blades at turkeys. I didn’t get it at first, when Troy said he had a golf bag of broadheads in his quiver. Now I do. With a heavy setup, and mixing/matching insert weights, you can use virtually any single head you want just use the corresponding weighted insert to keep the FOC the same. For poops and smiles I may even throw a leftover mechanical or two into a deer carcass just to see how mangled they get when they hit hard bone.

[@TheWVgoodguy22]

@@officerfoxtrot3633 wow 😮 you really are diving deep into the weeds as they say. Would be fun to experiment with different setups. As long as they fly true and the broadheads are sharper than factory you will be able to find something. I want to build my own arrows. The only arrows I have are prefletched with Blazers. 340 Cabelas Xtremes Stalkers (9.3 gpi on 29 in draw) and Carbon Xpress Mayhem SDS (11.25 gpi and 45 grain outsert). I want to try heavier heads than the 100 grain Montec CS and M3 and the Stinger Buzzcuts

[@TheMereside]

I would like to ask a question regarding a trad bow set up, your videos are really great to watch and understand, but most of the time it’s about compound bows/ distance, my questions are shooting a slow longbow and only shooting sub 25 yards are there any disadvantages to a heavy arrow, my set up has been around 500 grains in total but now I know my form is good and I have just set up 28” arrow with 674 grains in total and 28.9 foc arrow flight is perfect can going too heavy be detrimental or is it still the same that even at slower speeds momentum works the same? Regards Wayne

[@officerfoxtrot3633]

Considering Troy was talking before about the Native people of another country still using 2000-3000 grain arrows for hunting, I’m sure you aren’t going to find the tipping point for benefit to detriment unless you really tried. If you’re shooting a 30# longbow and load up 1200 grains or better, you might have problems. But if you’re anywhere from 40-60#’s and shooting under 1000, I think you’ll be okay.

[@mikeredmond2739]

Dr. Ashby says that you should shoot the heaviest arrow you can while still maintaining an acceptable trajectory.

[@thesickhorseranch]

Awesome stuff, thank you!

[@davepoor5000]

Any future testing say for traditional bow say graphed from 10 and 20 yards... i know it will show most likley same results but adding a trad bow to the mix would be interesting to see.

[@RanchFairy]

May do that!!!

[@jwopd]

Ranch fairy, what spine is being used on each individual arrow? Specifically the 589gr, 616 gr, and 670 gr arrow?

[@mikeharryhunt1709]

" willy whacker," now your talking my language..

[@RanchFairy]

First

[@Favorites2499]

I know you probably hear this alot and are getting sick of it. I know Ed's study is with a stick bow. What does that 650 grain arrow going 190 fps momentum equate to on a modern day set up. Would this equate to 495 grains at 285 fps. I am just throwing random numbers out there. Also I plan on getting a lab radar and will be more and happy to send you my data.

[@hall0341]

That's a lot of folks question. If we knew the FPS of the bow at impact we could calculate the momentum

[@bigz5262]

I think that’s why he’s saying to shoot for 550 instead of 650

[@timbow50]

Big Z my take from the tests is that 550 grains is about the magic weight from the equipment he used. Now, for me shooting 58#s @ 27 1/2" DL from a Ritual 550 grains the trajectory is dropping like a big rock. Yea, I know trajectory drop really isn't too important as you set sights for that. Whitetail and Mule deer aren't a problem for my 427grains but a big old boar might be????

[@bigz5262]

@@timbow50 trajectory is somewhat important. He normally says aim for the heaviest arrow that still gives you a trajectory you’re comfortable with. The light/heavy debate is fun to geek out on but arrow weight is pretty low on Ashby’s list of penetration factors. Make sure you’re bow is tuned, you have a strong, sharp broadhead, and you can hit where you’re aiming

[@timbow50]

Big Z I realize all these tests are just numbers in the real world but there's some good info here. For me I've pretty much been using hunting arrows in the past 25 years at least that are in the 400-425 grain area. This weight gives me a decent trajectory to be used with a three pin sight. Of the many deer I've taken only one was not a pass thru because I hit the front leg bone dead center. It still got her bad enough to fall about 100 yards away. In the past I was able to shoot 60-62 lbs at 27 1/2". Now 58#s is more comfortable ha ha! And I have always used fixed blade heads. Either Slick Trick Standards or Magnus Black Hornet serrated. These just seem to slice thru animals like they are warm butter.

[@jakebeaudoin4390]

Did you see the bowmar bow hunts in Africa?

[@RanchFairy]

No

[@steve8828]

I would love to see you take this one step farther and analyze the arrow trajectory. The reason people want lighter/faster is flat trajectory. I personally have moved up from 405 to 470 with my 60# bow. The trajectory is not as bad at 60 yards as expected it to be.

[@garrettstraffon608]

470 is heavy. And if you plan on shooting 60 yard shots you can’t have heavy arrows like that. For whitetail Atleast they will duct it and probably be turned by the time the arrow gets there

[@WM-jy9dz]

most people (count me in) are not concerned about trajectory, but about the time the arrow needs to reach the target to minimize the error margin due to deer ducking the arrow. ......something from another "test lab" kzbin.info/www/bejne/f4i7iIh4jLimsM0&ab_channel=GrowingDeer.tv ...

[@steve8828]

@@garrettstraffon608 I routinely practice at 70 yards. I am not a heavy arrow guy, but I was amazed at what I did not loose with this set up. I tried a 420 grain, then 445 grain, and finally the 470. Now my 405 grain arrows have killed deer for years, but this year I decided to play. I expected these arrows to “fall off a cliff” at longer distances, but they don’t. I don’t plan on taking a 60 or 70 yard shot. I just like practicing out there.

[@steve8828]

@@WM-jy9dz I have seen this video. When I first started bow hunting, the fastest bow on the market was below 200 FPS and we still hit the mark.

[@garrettstraffon608]

@@steve8828 yea they say practice at farther distance than what you plan to shoot. My arrow is about 425, I actually did notice a diff when I went up to about 510. And I even noticed a little drop when I went up just 25 more grains and that was 450. But the only thing I switched is a cut on contact head. All of this heavy arrow stuff is true the proof is there, but I want a flat fast shooting now and I’m pretty good with ethical shots so I’ll take my chances, I’m not big hunting or Cape buffalo hunting. I’m hunting whitetail that’s duck arrows. Yes you can aim a little low but with a heavy arrow he might not only duck he might turn by the time it gets there, I just believe in a middle weight set up, if I hit the shoulder that is my fault and I just don’t plan on doing that

[@SparkleDonkey]

I'm a bit late to the party here but this was really interesting. As a trad guy I'm pretty amazed at the speed and distance that you can get from a compound bow. For me, my bow maybe makes 192 fps on a good shot but I push 650gn and my max range is 20 yards. I'm working on a set of heavier arrows when my new grizzlies arrive. Looking forward to getting everything all tuned up.

[@ronlongwellphoto]

Fan-flippin'-tastic! And glad to see Rob Neilson's test on the Ashby Foundation website. Very enlightening! It's not just about momentum numbers; broadhead design is a critical piece of this puzzle as well. I'd been wondering if I just got the right momentum numbers if everything would sort itself out. It depends on the broadhead. Good stuff!

[@justinsalzl1517]

I read the report too. Last year I shot the Tuffhead Meathead 265 with the Sirius Apollo at 740 grains and loved it. It’s a 3:1 single bevel. This year I’m shooting the Tuffhead Evo 200 on the Sirius Orion at 630 grains. And I lowered my draw weight 5 lbs, but increased length an inch. Should be a interesting comparison. But I doubt I’ll have or take the exact same shot angle again.

[@justinsalzl1517]

Either way, the broadhead does matter. And I think the magic momentum number, at least from glancing at his charts, is around .62. But it’s late and maybe I didn’t fully grasp it.

[@drewsroo]

The sharpness of the broadhead matters too and can be measured on a machine. This very much should be an included factor in future testing.

[@mikeredmond2739]

I've been waiting for this one. Great proof of concept, and exactly what our sport needs to know. SUPPORT THE ASHBY FOUNDATION!!

[@danielely7437]

Why can’t u use accelerometers to measure impact? Possibly use blunt tips and see what the difference is in force. Maybe that’s a dumb idea.

[@matthewmoore856]

Science!

[@DustinApple]

Thanks Troy & Darrel keep educating the archery world. I see a minimum momentum number for each kind of game. you wouldnt shoot bird shot at a deer why would you shoot twizzler loads at a Elk? While that 400gr arrow might work in the south on 120lb deer, turkey, & pronghorn, everything else is going to require high brass loads.

[@km6731]

If I remember one thing from science projects, it would be "replicates" . Can't take the results of one outcome and make it a fact. Have to have multiple trials. For example, shoot each arrow 3 to 5 times.

[@davidayres9865]

And here I thought I was analytical when it came to shooting my arrows...

[@Mike-vk6mo]

Are you connected with @SmarterEveryDay?

[@arkieoutdoors397]

Is this data available in excel anywhere?

[@RanchFairy]

Not currently

[@sunshinedetail309]

Audio sucks but other than that good info wish more people payed attention to the ranch fairy. Be a lot less wounded animals and less headaches that's for damn sure

[@rootnpearl]

High speed camera of you shooting your test subjects (a.k.a. Pigs) would be great to see.

[@ZJ_Rubicon]

This all makes so much sense! I don't understand people that think this doesn't work.

[@davidfrette7721]

Man I love this and the fact that you are continuing to go deeper with the high speed camera.

[@greekmaster1001]

And this is the exact reason why I donate to Ashby foundation....

[@brianbennett8445]

Nice job on the details! Can not argue with facts.👍

[@N1outdoors]

Good stuff and clear explanation Troy!

[@SuperToehead]

My money is on momentum every time old son! Great illustration

[@allenprice2425]

Thanks for another great informative video 🏹

[@Bowstringdotcom]

I always put it this way, if you throw a ping pong ball, and a golf ball at the same speed (or close to the same speed) at your drywall in your home, which one is gonna go through the wall? No-one ever gets the answer wrong. Or, if I throw a ping pong ball at you as hard as I can, and then a golf ball, which one are you gonna try and duck and cover from? No-one gets the answer wrong. Heavier projectile will hurt more when it hits, its harder to slow down....

[@WM-jy9dz]

sorry, but your analogy is flawed (if it refers to a bow): the quantity that would hurt you (or the wall) is called kinetic energy (KE) that is calculated KE = 0.5 x MASS x SPEED^2. The KE gives the ping pong ball and the golf ball the momentum, and this is calculated as SPEED x MASS. If you don't change the draw length and poundage, your bow will launch the lighter arrow and the heavier arrow with pretty much the same KE (there are internal losses that become more and more relevant the lower the GPP is) but obviously with significant DIFFERENT VELOCITIES. (Try to run up the stairs as fast as you can, and than do the same with a 100 pound backpack and you get the idea). I know it is quite common to use this analogy, but if it would be used correctly, thus comparing apples (launch KE) with apples (launch KE), the ping pong ball would have an insane high velocity (due to the structural weakness it would be challenging to accelerate it to this speed) - the lighter ping pong ball wouldn't loose much of the KE due to air friction / drag (due to the insane higher speed) considering that the throw would be only over a few yards (over 40, 50 ....80 yds and it is a total different picture). While the momentums would be different (see equation), those different momentums would translate still to the same KE that would hit the wall or you thus would inflict the same pain.... So, also light items can hurt you - think about a bullet that can be significant lighter than an arrow, but is still able to do a lot of damage due to the high speed. (All based on the principle of conversation of energy).

[@Bowstringdotcom]

@@WM-jy9dz ........ Its not intended to be watertight data. It is intended to be a layman concept to comprehend what happens when you hit dense tissue or bone with projectiles of varying weight, and what that weight does when it has resistance....its intentionally not data based. If you and I show up to the archery range and both give our dissertations, I'll leave with curious friends, and you'll leave with people who aren't interested in talking to you. Another way to demonstrate this would be to give you a slingshot, and some paintballs, give me a slingshot and some marbles, and you and I have a shootout until someone says "uncle"......

[@WM-jy9dz]

@@Bowstringdotcom I know and agree (I mentioned that this is a quite common, but wrong, analogy), but that's the difference between science and small talk respectively the difference whether you want to entertain your mates or whether you want to optimize your setup.

[@LUCKY-gi6fj]

So in Laymans term you have a smart car and a Cadillac both traveling at 60 mph when they hit something the Cadillac is going to do more damage because it has more weight behind it even though they both are traveling the same speed ??? Sorry for the example just trying to understand it in simple terms.

[@RanchFairy]

You could also increase the speed of the smart car ALOT and it still wouldn't have the momentum.

[@brianpfleuger]

Momentum is also not just an "amount"... it is a vector. Momentum has direction. A big heavy car that runs you over wants to keep going straight over you... a bicycle might bounce off to the side. Light arrows deflect (more often), heavy arrows go straight (more often)... and *keep going* straight. A heavy arrow will have high momentum... slowing it down in a short distance (a bone) requires a lot of force (force = change in momentum divided by the time the change took)...force breaks bone. Kinetic Energy from light, fast arrows just makes noise. Kinetic Energy is scalar and can be lost in any number of ways (and in any direction)... momentum is always "forward". Poor RF... I feel your pain in these videos, it's so hard to explain this stuff succinctly. You do a great job, sir. ;)

[@RanchFairy]

@@brianpfleuger we are getting there

[@carypeaden4147]

Ballistics of firearm projectiles is discussed in three categories: internal, external, and terminal. That is also a good way to think about archery. Internal ballistics deals with converting the stored energy of the bow or powder into the projectile while in or on the machine (bow/gun), external ballistics deals with the projectile in flight to the target, and terminal ballistics is what happens once the projectile reaches the target. I think your data/charts are showing the efficiency advantage of heavy arrows for the first two. More energy and momentum is being stored in the heavier arrow at launch than in the lighter arrows, so that shows the efficiency advantage in internal ballistics. Then the increased velocity erosion during flight (of lighter arrows over heavier arrows) while mass stays the same demonstrates the efficiency of heavier arrows in flight. I guess penetration demonstrate the efficiency advantage of heavier arrows upon impact. I guess the trajectory counter to all of this is that we still must hit what we are aiming at. In firearms a hit with a 22lr is more deadly than a miss with a 50BMG.

[@WM-jy9dz]

the launch KE is pretty much the same for the same bow - heavier arrows are only slightly more efficient. The bigger KE loss is caused by the air friction / drag due to the higher speed of the lighter arrow thus pending also heavily on the distance. Wrt momentum threshold: 0.57 pounds*sec is considered as the suitable threshold acc. to Ashby for big game (e.g. cape buffalos) - with a 31" draw length and 66# plus I can achieve this easily with a 430 grain arrow: I get 0.57 pounds*sec at 300 fps - for longer distances I can go up to 68# ....70# to compensate for the drag ....and I don't shoot cape buffalos....

[@dieselpusher2548]

Just passin through the city baby

[@davidayres9865]

RF dropping knowledge again!

[@chucklewis5396]

Great vid!! Keep them coming brotha!

[@darrylsmijan9123]

You lost me in the first couple minutes lol

[@mikeroland3720]

Another great video thank u sir

[@refuel84]

Just curious how you combat all the backlash guys spew about arrow speed, I personally don't care if my arrow flys at 280fps at 20 yards vs 340. But there's so many folks out there trashing us that follow Dr. Ashby's studies and they only want to argue how slow our arrows are.

[@DigtoDef]

Perhaps the argument should be how slow all arrows are compared to the speed of sound

[@WM-jy9dz]

@@DigtoDef the response time of a deer for a visual trigger is shorter compared to a sound trigger - now if you count this in (some hunters take the shot when the deer is quartering in) the time a slower arrow needs to reach the kill zone will increase the error margin dramatically if the deer ducks - but at least you get still good mud penetration when you miss 😁.

[@ronmacdougall9612]

Good info