HuntStand Hunting App
KE or Momentum?
Equipment
Contributors to this thread:
ohiohunter 01-Aug-20
DanaC 01-Aug-20
altitude sick 01-Aug-20
Mike in CT 01-Aug-20
Buglmin 01-Aug-20
Kurt 01-Aug-20
Treeline 01-Aug-20
Spiral Horn 01-Aug-20
Franklin 01-Aug-20
Grey Ghost 01-Aug-20
ohiohunter 01-Aug-20
Grey Ghost 01-Aug-20
ohiohunter 01-Aug-20
Medicinemann 01-Aug-20
Grey Ghost 01-Aug-20
Mike in CT 01-Aug-20
Will 01-Aug-20
ohiohunter 01-Aug-20
Grey Ghost 01-Aug-20
ohiohunter 01-Aug-20
Grey Ghost 01-Aug-20
ohiohunter 01-Aug-20
Grey Ghost 01-Aug-20
Norseman 01-Aug-20
ohiohunter 01-Aug-20
Grey Ghost 01-Aug-20
ohiohunter 01-Aug-20
Grey Ghost 01-Aug-20
ohiohunter 01-Aug-20
ohiohunter 01-Aug-20
Grey Ghost 01-Aug-20
Norseman 01-Aug-20
TEmbry 01-Aug-20
Mike in CT 01-Aug-20
ohiohunter 01-Aug-20
Jaquomo 01-Aug-20
bb 01-Aug-20
ohiohunter 01-Aug-20
Mike in CT 01-Aug-20
ohiohunter 01-Aug-20
ohiohunter 02-Aug-20
Kurt 02-Aug-20
ohiohunter 02-Aug-20
ohiohunter 02-Aug-20
ohiohunter 02-Aug-20
Medicinemann 02-Aug-20
ohiohunter 02-Aug-20
ohiohunter 02-Aug-20
Kurt 02-Aug-20
Mike in CT 02-Aug-20
altitude sick 02-Aug-20
Grey Ghost 02-Aug-20
ohiohunter 02-Aug-20
ohiohunter 02-Aug-20
ohiohunter 02-Aug-20
Grey Ghost 02-Aug-20
ohiohunter 02-Aug-20
Grey Ghost 02-Aug-20
ohiohunter 02-Aug-20
Mike in CT 02-Aug-20
ohiohunter 02-Aug-20
spike78 02-Aug-20
ohiohunter 02-Aug-20
HDE 02-Aug-20
DEMO-Bowhunter 02-Aug-20
ohiohunter 02-Aug-20
Norseman 03-Aug-20
Jaquomo 03-Aug-20
Grey Ghost 03-Aug-20
Jaquomo 03-Aug-20
Norseman 03-Aug-20
Grey Ghost 03-Aug-20
DEMO-Bowhunter 03-Aug-20
Jaquomo 03-Aug-20
DEMO-Bowhunter 03-Aug-20
spike78 03-Aug-20
bb 03-Aug-20
Matt 03-Aug-20
ohiohunter 03-Aug-20
Medicinemann 03-Aug-20
Norseman 03-Aug-20
ohiohunter 03-Aug-20
Mike in CT 03-Aug-20
ohiohunter 03-Aug-20
Mike in CT 03-Aug-20
ohiohunter 03-Aug-20
Mike in CT 03-Aug-20
Grey Ghost 03-Aug-20
ohiohunter 03-Aug-20
Mike in CT 03-Aug-20
Jaquomo 03-Aug-20
ohiohunter 03-Aug-20
TEmbry 03-Aug-20
ohiohunter 03-Aug-20
Grey Ghost 03-Aug-20
Mike in CT 03-Aug-20
Norseman 04-Aug-20
ohiohunter 04-Aug-20
Grey Ghost 04-Aug-20
WapitiBob 05-Aug-20
HDE 05-Aug-20
Grey Ghost 05-Aug-20
WapitiBob 05-Aug-20
Grey Ghost 05-Aug-20
HDE 05-Aug-20
WapitiBob 05-Aug-20
From: ohiohunter
01-Aug-20

ohiohunter's embedded Photo
ohiohunter's embedded Photo
ohiohunter's embedded Photo
ohiohunter's embedded Photo
ohiohunter's embedded Photo
ohiohunter's embedded Photo
Let’s toss a wrench in things.. found this on Facebook.

From: DanaC
01-Aug-20
We're given the figures for ke but not momentum. Do both, and graph both, then we'll have some basis for comparison.

01-Aug-20
400 grain setup is 54 slugs 650 grain setup is 71 slugs

Big difference in momentum

If you tried the same thing at 30 yds you would see very little drop 40 yds is where the drop starts with that setup

From: Mike in CT
01-Aug-20
I've always advised that one should look at KE as a baseline assessment of their set-ups potential to produce for game, particularly when targeting big game such as elk. KE is what your set-up generates at the bow and if you're marginal initially than your set-up is a poor choice if you're shooting at any appreciable distance.

Momentum, on the other hand correlates well with how much penetration your arrow will have at the target; physics dictates that a heavier object will have greater momentum and for that reason I advise placing more emphasis on developing a set-up that will focus more on momentum.

Now, if you are capable of comfortably shooting high poundage you can have the best of both worlds and have a fast (but not warp speed ala a 340 grain arrow) and still have good momentum at the target.

From: Buglmin
01-Aug-20
I've argued and argued this. And for some reason, everyone thinks the momentum you have three feet in front of the bow is the same momentum you have at 20 and 30 yards. Chronographs and momentum calculators will show you that when you start dropping arrow speed, you drop momentum, faster then you think. Momentum is measured in slugs, and three feet in front of you bow, .400 slugs is a lot. But at 30 yards, when you drop .050 slugs, that's not a good thing. We can argue all day, but chronographs and calculators show different results then the guys preaching high foc heavy arrows claim.

From: Kurt
01-Aug-20
Interesting that the lighter and faster arrows penetrated deeper in the ballistic gel in the photo above.

From: Treeline
01-Aug-20
Ran several of my arrow combinations on the online Realtree calculator.

Interesting that most of my setups were called out as only good enough for antelope or “bantam weight” game. Those setups have performed extremely well on moose, elk, caribou, sheep, mountain goats, red stag, feral hogs, white tails, bears, lions, mule deer, axis, blacktails, antelope, coues, etc, etc, etc over the years.

My arrow setup that blew through a buffalo, breaking ribs, and stuck in the ground 20 yards on the other side was considered OK for whitetails at 39.8 ft-lbs and .468 slugs.

My setup generates far less energy and momentum that this guy’s wife’s setup. Still have killed plenty of critters from Argentina to Alaska plenty dead!

Modern compounds generate an amazing amount of energy and momentum, even with very low draw weights. Heck, even draw weights that would be considered “kid’s” or “youth” draw weights generate more energy and momentum that very heavy traditional bows.

If bigger stuff can be killed effectively by trad bows, pretty much any modern compound is more than enough!

From: Spiral Horn
01-Aug-20
While they are always a good place to start and good info to have there is far too much emphasis on raw initial energy numbers. There are many other variables in play that will determine penetration on a game animal at a given distance — terminal momentum, arrow material and diameter, broadhead material and design, density of the animal tissue impacted, etc.

For North American game I’ve been very successful with a 70lb 29.5 draw bow shooting a 455gr arrow (total weight) @ ~295-300fps. Unless it solidly impacts a major bone, usually get a pass-through on everything including Moose.

Now thick-skinned game is completely different. Night and day on density of animal tissue. A Whitetail setup is a fool’s errand on a Hippo or Cape Buffalo. Here, closer shots with heavy arrows and razor sharp, tool steel 2-blade heads are key. Even so called “bleeder blades” will reduce penetration. My personal favorites are original German Kinetics.

Anyway, I know some guys love tinkering with bows and arrows, but my primary interest is their effectiveness as hunting tools. Once I construct a setup that works well on game and I’m confident in I’ll generally stick with it until something appreciably better comes along. This builds familiarity and confidence for the moment of truth.

From: Franklin
01-Aug-20
Many moons ago when compounds were in their infancy we played around with speed vs weight and KE on certain game. Nowadays it`s almost a obsolete thought for an adult male. I can see where it has a place in youth, females or the elderly that can`t pull higher draw weights.

Todays bows, arrows and broadheads have all but eliminated the question.....except for those that are always in search of the bowhunting Holy Grail.

From: Grey Ghost
01-Aug-20
The other factor to consider is arrow flight tuning. High KE and/or momentum doesn't do a lot of good if the arrow is flying sideways, fishtailing, or porpoising. Take the ballistic test above for example. It's clear that the arrows entered the standard target at several different angles, which leads me to believe the shooter didn't re-tune his bow for each different arrow weight. If not, then it's not really a valid test.

Matt

From: ohiohunter
01-Aug-20
Tuning is for forks.

The data is linear for the parameters proposed which would not suggest one variable was favored over another. Even if he had evidence of every arrow tuned someone would say “eh, I don’t shoot those kind of fletching”... IMO f the tune, all things considered this is the most complete display and test of its kind I’ve seen to date.

One thing I would’ve like to have seen, and it’s difficult to do, is down range ballistic gel penetration. I think the higher slugs would start to shine.

From: Grey Ghost
01-Aug-20
"..f the tune."

Seriously? So you're saying a test that involves a perfectly tuned bow/arrow weight setup isn't going to show different results than a poorly tuned setup? Right.

Look at the arrow angles in the first picture you posted. It's clear to me the shooter's setup was tuned for the lighter arrows, as they both entered the target at the same straight angle. Each progressively heavier arrow pair shows evidence that they weren't flying true, which adds a larger drag coefficient, and therefore affected the results.

I ran the numbers using the shooters own speed and weight information. I assumed all the arrows were 30" and fletched identically. The difference in drop between a 400 gr arrow flying at 309 fps and a 650 gr arrow flying at 246 fps is 19" at 50 yards. That's based on physics and math. It's difficult to see in your fuzzy picture, but it looks like the shooter's tape measure is showing around 22" of difference. That tells me he wasn't getting true arrow flight out of the heavier arrows.

Matt

From: ohiohunter
01-Aug-20
Since “tune” is so important, please quantify penetration and trajectory differences between a perfectly tuned arrow and a slightly less tuned arrow. I’ll wait.

While I understand tune, it’s not the end all imo. Most rigs are not tuned. As For the test to argue the lighter arrows are better tuned therefore it completely negates findings is rubbish. Your argument is 100% assumption, how do you know his rig Is not tuned... how do you know he doesn’t have torque issues? So yes... f the “tune”.

Let me tap your expertise... pure center shot is achieved for perfect fp tune. How much, if any, is that tune off for a different arrow same diameter?

If you’re gonna preach tune one would think you know how to tune. Js

From: Medicinemann
01-Aug-20
Several years ago, while preparing for an African elephant bowhunt, I contacted Ricardo Longoria. Ricardo had done about 5 elephant hunts at that time. He has killed several bull elephants. What I found most interesting about Ricardo's experiences is that he had two pass through shots...on elephants!! In both cases, he was shooting lower poundage bows (80#) and lighter arrows (800 grains) than what most elephant bowhunting guides suggested.....his single biggest differentiating factor?.....he had his bow tuned with a hooter shooter until he had PERFECT arrow flight. The result? Since switching to a bow that was extremely well tuned, he was dramatically outperforming many higher poundage bows shooting heavier weighted arrows...…. Bow tuning is a critical factor to me as a result of Ricardo's shared information and shared experiences.

From: Grey Ghost
01-Aug-20
"While I understand tune, it’s not the end all imo. Most rigs are not tuned."

That tells me everything I need to know about your archery ballistics knowledge. You are right, however, most "rigs" are not tuned, because most archers don't know how to properly tune a "rig". That's also a reason why mechanicals are so popular. Guys can throw on a mechanical of equal weight to their field tips, and they will group the same, regardless if the bow is tuned properly, or not.

Head weight, arrow weight, length, spine, and diameter, FOC, fletching type and placement, even the nock type...all will change the tuning slightly. And of course, the archer's form, or lack thereof, will also affect how the bow is tuned. There is no one perfect tune that will work for every arrow combination. Arrow diameter is just one of many variables that will affect tuning. That's were the test you posted is flawed, unless the shooter took the time to re-tune his bow for every different arrow weight and spine. I suspect he didn't.

Matt

From: Mike in CT
01-Aug-20

Mike in CT's Link
Excerpt from a great article that explains KE and momentum "The lighter arrow has 10.22 percent more disposable net force (and 123.2 percent more kinetic energy) than the heavier arrow but, because of its higher velocity, it is met by four times the resistance to penetration. Which arrow will penetrate further in real tissues? Empirical evidence from the outcome studies provides an overwhelmingly definitive answer. Both the frequency and degree to which the heavier, slower, arrow out-penetrates the lighter one is of such a magnitude that it must be viewed as the norm.

From: Will
01-Aug-20
This is messy too - in that if one is basing their view on how their whitetail rig has worked, and others are basing it on Moose/elk/buffalo/hog's or what not the need gets messy.

Ironically, it seems one is likely best served with a sharp fixed head at the extreme ends either way - really light or heavy... With the former you need it to get as much penetration as possible with minimal resistance, with the latter you are doing it so you can get through heavy tissue/bone to get as much penetration as possible.

Most folks are in the middle some where and do just fine given they are hunting critters that approach works great for - deer, antelope, etc.

That's a cool read Mike - good one!

Ill second GG on the Tune thing. Better tuning = better flight = better energy down range and less resistance on entry. Regardless of head style chosen.

From: ohiohunter
01-Aug-20
How many times can we overstate the obvious about tune??? Am I the only one who sees mostly linear data here regardless of tune (of which NO ONE KNOWS the specifics) for what has been proposed? Does anyone arguing this understand the significance? Next thing gg will ask is was it a S wind or SE?

Help me understand the dilemma, so if all arrows were perfectly tuned the outcome would be exactly opposite?

From: Grey Ghost
01-Aug-20
Not sure what you mean by "linear data". I can tell you that tuning makes a HUGE difference in ballistics of an arrow. The same tune will not produce accurate ballistic information for arrows that differ in weight, spine, and FOC.

Additionally, the same bow and tune won't provide the same ballistic information from 2 different shooters. A bow and arrow setup HAS to be tuned for the specific shooter. A tune that works for me and my shooting form, is not likely to work for someone else.

And for the record, my comments come from helping literally hundreds of archers, every year, tune their compound bows when I was a sponsored competitive 3D shooter. I learned from some of the best archers in the business. So, I think I speak from knowledge that some archers don't have.

Matt

From: ohiohunter
01-Aug-20
That’s great and all, but you have not provided any information to deduct from the results to definitively dismiss significance. Again would your tuning abilities refute what has been proposed? Would your tuning ability reverse this mans results? What if all arrows shot were equally untuned?

For the record, since this APPARENTLY needs to be vocalized on every thread... no one is dismissing the efficiency of a properly tuned arrow. This horse is beyond dead, the bones are crumbling in the sun... no need to beat it one last time.

Gg. You’ve consistently been devoid of any question to site tuning as being the only reason these arrows performed they way they did. Please correct me if I’m wrong, surely you will.

From: Grey Ghost
01-Aug-20
James,

I'm not sure what earth-shattering data you think your posted ballistic test shows. Of course tuning isn't going to reverse physics, and cause heavier arrows to magically have a flatter trajectory than lighter arrows. That wasn't my point.

Your posted test shows 22" difference in drop between the lightest and heaviest arrows at 50 yards. If you actually run the numbers (there are several ballistic calculators online), there should have only been 19", all else being equal, including tuning. The reason your posted test was almost 16% off was likely do to lack of tuning. That was my point all along.

Matt

From: ohiohunter
01-Aug-20
How can you honestly and accurately calculate the trajectory based on the given information? Trajectory is only part of the equation and more less a byproduct. More importantly, hence the title, KE vs momentum. We all know same velocity the heavier projectile wins, but we can’t have pie n eat it too. So in the land of compromise something has to give, so what’s the best compromise? But like I said, this is a bit of a wrench relative to current topics.. I’m not after anything except not listening to tune this tune that tune tune tune. We get it. But to invalidate everything anyone does simply bc you did not tune this guys bow is a bit much, ya think?

So you are telling me every little thing effects tune, but equally every little thing will effect trajectory yet you use gross parameters to approximate drop then use your generalizations to refute real world evidence bc of a 3” discrepancy at 50yds. Do you not see the contradiction?

From: Grey Ghost
01-Aug-20
I haven't invalidated anything, James. I've just point out the inaccuracies of your posted test.

Again, I ask, what significant information are we to take away from your test? That heavier arrows drop more than lighter ones? Gee, that's shocking!!

Or, was the point of the test to show that 400-650 gr arrows traveling at 309 -246 fps, respectively, both have plenty of KE and momentum to kill virtually every animal we shoot at? If so, I agree.

However, if your test was suppose to show accurate ballistics information (ie: amount of drop difference between different weight arrows), then it's not very accurate for the reasons I've posted.

Have a great evening.

Matt

From: Norseman
01-Aug-20
Thanks for that great read. I remember reading that years ago by Ed Ashby.

“ To say this in another way, arrow momentum derived through increasing arrow mass results in a greater gain in penetration than does momentum gained by increasing an arrow’s velocity. This is true because the tissue’s resistance is increased by the square of the velocity.”

From: ohiohunter
01-Aug-20
I’ve not heard of the resistance of tissue relative to velocity, I wonder if it is fact or theory?

Matt, something tells me you probably have a lot of sisters. Still devoid of any and all questions. Good day sir

From: Grey Ghost
01-Aug-20
James,

I have 1 sister. What does that have to do with anything? And what does "devoid of any or all questions" mean? I don't have any questions about your posted test because it doesn't really provide any useful information. Yes, heavier arrows drop more than lighter ones do. I probably learned that in high school physics class. What did I miss?

Have a cocktail on me, and enjoy your evening.

Matt

From: ohiohunter
01-Aug-20
For god sakes forget the trajectory!!! How many ways can I type that? Will it help if I erase the picture?

From: Grey Ghost
01-Aug-20
So, please explain what point you are trying to make about "KE or momentum" on this thread. Or don't. It really doesn't matter to me. It's your thread.

Matt

From: ohiohunter
01-Aug-20
Medicinemann, do you think Ricardos experience was due optimization of speed & weight? Certainly we know the best performing projectile lies in between extremes, I’m wondering if Ricardos set up was closer to the peak of the curve where as the tradition of heavy arrows pushed other hunters towards an extreme? Do you know What kind of penetration He got on the other 3 elephants?

From: ohiohunter
01-Aug-20
Matt, there is no point. I’m not arguing anything except you bc you want to tune everything. I posted nothing but one mans test, which for once someone used ballistic gel correctly, with the statement of throwing a wrench into things... you took it from there. Please revisit original post for confirmation.

From: Grey Ghost
01-Aug-20
Thanks for clarifying that there was no point to your thread.

All the best,

Matt

From: Norseman
01-Aug-20
Read the paper. It is proven in the math.

From: TEmbry
01-Aug-20
I won’t speak for the OP, but I certainly find results like this interesting. I don’t view it as a KE vs Momentum debate but rather speed (ie arrow drop) vs penetration issue. If a 400-450 grain arrow penetrates nearly as well as 600+, there’s a rather convincing argument to be made to go on the lighter side of the spectrum for spot/stalk hunters who are often shooting on the fly without known yardage markers that are had in treestand settings. Misranging animals by a few yards is far more critical slinging 600 grain arrows vs 400.

It’s obviously a scale of diminishing returns when considering arrow weight (in both directions).... you have to decide where that happy medium is and to date there isn’t one definitive answer for everyone

From: Mike in CT
01-Aug-20
Tembry,

Read Norseman's post above yours then refer to link in my post; physics will tell you irrefutably that a heavier arrow will penetrate better than a lighter, faster arrow; the math is conclusive.

Ohio,

Matt's point which for God knows what reason you consistently miss is that tuning is paramount to consistent, proper arrow flight; absent any indication from the author that he re-tuned his bow to each different arrow I have to agree with Matt's point that the drop is greater by an appreciable amount vs what should be expected.

I'd add that the ballistic gel results seem to bear this out; heavier arrows should consistently achieve greater penetration; as they don't appear to in the photo and the physics is plain that they should the only variable to ascribe the deviation to is poor tune and resultant poor arrow flight for the succeedingly heavier arrows.

I applaud the intention of the author you cite, the execution not so much.

From: ohiohunter
01-Aug-20

ohiohunter's embedded Photo
ohiohunter's embedded Photo
Better view

From: Jaquomo
01-Aug-20
Wonder what the old time bowhunters argued about over whiskey at night, before KE and momentum existed?

From: bb
01-Aug-20
LMAO, Glad I never knew about it, BBS (before bowsite) I'm sure I would have never killed anything.

From: ohiohunter
01-Aug-20
Really? How do you know he didn’t “TUNE” his arrows? How do you know he shoots the lighter arrow? Just bc this guy is off by 3” top to bottom at 50yds everything must be dismissed and his bow is completely untuned bc it didn’t duplicate a generic computer app? Split the difference, that is literally 1.5” Off North and south. I guess you guys are plinking 12 rings at 50yds... I salute you and will attend the next IBO worlds banquet to shake your hand and buy you a beer.

From: Mike in CT
01-Aug-20
Ohio,

What I shoot, what Matt shoots or what anyone shoots is irrelevant to this discussion; the laws of physics do not support the results the author shows unless accounted for by the likeliest variable, tuning.

Also, please don't hyperbolize as it detracts from the discussion; neither Matt or I has ever said the bow was completely untuned, merely that the results did not match what should occur with a well-tuned bow for each successive arrow.

I posted a link to help you better understand the physics; if it would help I'll post a link to help with your understanding of the English language.....

From: ohiohunter
01-Aug-20
Hyperbolize? I think complaining about 3” vertical deviation at 50yds is hyperbolized and is well within anyone’s skill set. Hell most, including myself, would love to shoot 3” groups at 50. I also think if you’re going to criticize someone’s ability to shoot you’ should be better. Btw I see no link. I see it now

I also think criticizing the mans vertical dispersion without knowing his arrow parameters is an act of futility. Especially when arguing every minor detail greatly influences tune. I cannot foresee one arrow flying true then the next arrow slapping the target.

Do you or anyone have evidence of a similar test?

From: ohiohunter
02-Aug-20
I’ll propose this. Assume all arrows are tuned (hard, I know). What arrow characteristics, weight distribution, could possibly support this guys results? I do find it oddly ironic this guy went up in weight in perfect 50gr increments.

Upon further investigation.. I did assume this guys setup was losing something somewhere in the sense of diminishing returns hence his results. But his energies did continue to climb in both p and KE.

From: Kurt
02-Aug-20
One variable not mentioned is the two shaft spines, .250 and .300 have slightly different outside diameters, with the stiffer shaft having 5.4% larger cross sectional area to impede penetration...on the 550, 600 and 650 gr arrows.

From: ohiohunter
02-Aug-20

ohiohunter's embedded Photo
ohiohunter's embedded Photo
Hmmmm

From: ohiohunter
02-Aug-20

ohiohunter's embedded Photo
ohiohunter's embedded Photo
Seems there was more attention to detail for this than originally thought.

From: ohiohunter
02-Aug-20

ohiohunter's embedded Photo
ohiohunter's embedded Photo
I digress, the penetration is not linear. The first angle seemed so with a plateau but a better picture shows penetration as An inverted bell curve. Suggestive of potentially equalling or exceeding his 4-450gr arrow penetration with a heavier arrow but with an obviously massive trajectory sacrifice.

From: Medicinemann
02-Aug-20
Ohiohunter, Yes. It's possible. I know that they were not pass throughs....nothing more.

The two things that I really embraced from Ricardo's previous experiments and research, were that tuning a bow was of paramount importance, and that small diameter, stiff spined arrows out performed the other combinations.

From: ohiohunter
02-Aug-20
Looking more into this guy he’s not some schmuck with ballistic gel. He’s far more accomplished In the hunting world than I’ll ever be. Industry professional with BighornS, dall, mtn goat.. but back to my original statement.. a big ol wrench!

Gg I hope the previous posts answers all your tuning prayers. Seems the only slight variation is what Kurt pointed out about shaft diameter.

From: ohiohunter
02-Aug-20
Medicinemann, pretty sure it was you who gave me the Mathews safari bow. I love watching people try to pull it back, I’m still looking for a shorter cam so I can shoot it. I think my buddies scale put it over 100# I can’t remember exactly. Thank you again.

From: Kurt
02-Aug-20
One variable not mentioned is the two shaft spines, .250 and .300 have slightly different outside diameters, with the stiffer shaft having 5.4% larger cross sectional area to impede penetration...on the 550, 600 and 650 gr arrows.

From: Mike in CT
02-Aug-20
Ohio,

I think your understanding of hyperbole is flawed; explaining that the laws of physics don't align with the results is positing facts; the hyperbole is yours in exaggerating what Matt or I stated with regard to tune.

Speaking of which, the subsequent posts offer too little information; what does this person consider constitutes tune? Some think paper tuning at 3' and getting a bullet hole constitutes tuning; that is merely capturing one moment in time and it's part of the whole, not the whole.

The ballistic gel photo shows better detail on depth of penetration and supports Matt and my position; the laws of physics don't bend to anyone regardless of credentials; you're arguing from authority and that's a flawed argument.

FYI, again, what Matt or I can accomplish with regard to shooting is irrelevant; grow a thicker skin as I have no inclination to indulge your or anyone else's inability to absorb valid criticism.

02-Aug-20

altitude sick's embedded Photo
altitude sick's embedded Photo
I don’t need any of the pictures above. It’s very clear to me when I shoot heavier arrows from the same bow they penetrate the target and animal better.

I did start out by reading and listening to others that heavy is better. But then went and verified it myself.

I’ve posted this pic before but it is worth showing again. Real life penetration

I was dialing in a new set up, a 1028 grain arrow 75# Vertix.

and stepped back to 40 yards. Missed my large 3D target and drove the IW 250 Broadhead through a very large bag target. That was behind the McKenzie target Try shooting a Broadhead through a large bag target with a 450 grain setup.

From: Grey Ghost
02-Aug-20
If that guy "perfectly tuned" each arrow setup, they wouldn't be angled all over the place in the target like the picture shows. And his ballistic gel results wouldn't seemingly defy the laws of physics.

Sorry, but there's really no useful information to be learned from this test, other than proper tuning means everything with respect to accurate ballistic information.

Matt

From: ohiohunter
02-Aug-20
Altitude, I’ve blown through an heavy bag with a thick nylon material backing hit the septic lid and disappeared in the woods. It was nothing fancy acc with a wasp sst... I blame the bh, I love wasps sst tip. Or it could’ve been a soft spot of some sort, but for the record I’ve had arrows bounce off this target. The arrow planed and missed my McKenzie, the bag was a back stop.

***Haha, I just realized with both missed the same target, but I was a broke kid so my McKenzie was just the replacement front leg.

Btw.. gg. The guy literally posted every paper hole for each arrow.

From: ohiohunter
02-Aug-20
I haven’t been to Comp to read all Ashby’s paper but what little I did read he said he could not duplicate real world findings with just ballistic gel. He had to cover the gel with another material. I wonder if what is illustrated here is the exact conundrum Ashby faced.

From: ohiohunter
02-Aug-20
Kurt, food for thought. The 500 & 550gr arrows are both the same spine and diameter, so basically apples to apples with the 500 prevailing. CORRECTION: 300 was used for 400-500.. change to 250 for 550.

From: Grey Ghost
02-Aug-20
"Btw.. gg. The guy literally posted every paper hole for each arrow."

As Mike mentioned, a bullet hole thru paper really doesn't mean much. That's just one moment in time thru-out the arrows entire flight. Even a badly tuned setup will punch a bullet hole thru paper at some point down range, as the arrow is constantly correcting itself during flight.

I don't understand why you continue to think this guy can magically defy the laws of physics with his test. The reason why his lighter arrows showed more penetration in the ballistic gel is because they were flying more true than the others. That's really the only logical conclusion.

Did you even read the article Mike posted? I know math is hard for some, but he does a good job of explaining arrow penetration in layman's terms, after you get past all the math. The bottom line is a heavier arrow will always penetrate more than a light arrow , because momentum derived from mass creates less resistance in tissue than momentum derived from velocity.

I'm sorry that doesn't jive with your Facebook study, but its indisputable based on the laws of physics.

Matt

From: ohiohunter
02-Aug-20
So now the arrows weren’t tuned enough! LOL.. you have got to have female dna somewhere in you, perhaps XXY chromosomes. I don’t know why you continue to argue, but I’m a sucker for a fight. I am not pushing anyone’s agenda! I found this interesting and it was done as sound as I’ve ever seen.

Have I once, during all this or any other thread, said lighter arrows out penetrate heavier arrows? Pretty sure I have not yet you act like I’m on here trying to sell you a shamWOW and a 380gr arrow. You’ve done nothing but try to discredit this guy, not a single compliment to his efforts. From what I can tell the guy is stand up with an extensive archery resume and submerged in the industry. I find it most ironic you criticized his 50yds vertical dispersion Of 3” when you strive for 5” groups. Can you not see your own hipocracy?

From: Grey Ghost
02-Aug-20
Woah, back up a moment, James, and take a deep breath. Nobody is trying to discredit your Facebook buddy. We are disputing his less than accurate results, however, and offering the most logical reason why his results were flawed. That's all.

And I didn't criticize his 50 yard "vertical dispersion", whatever that means. I pointed out that the vertical drop of his heaviest arrows was off by 3", and I explained why that probably happened. The guy is obviously a good shot, based on his groups. He's just not much of a ballistics technician.

Now, exhale, and try to grow some thicker skin.

Matt

From: ohiohunter
02-Aug-20
That gave me a laugh. You guys are funny

From: Mike in CT
02-Aug-20
"You’ve done nothing but try to discredit this guy, not a single compliment to his efforts."

I may just reconsider getting you that link to a primer on the English language after all given I posted this:

"I applaud the intention of the author you cite, the execution not so much."

"Have I once, during all this or any other thread, said lighter arrows out penetrate heavier arrows?"

Have Matt or I ever done anything but post the undeniable facts as relating to the laws of physics? Is your rule of thumb "when in doubt, bring a straw man argument into the mix?"

"That gave me a laugh. You guys are funny."

I'd be happier with a more mature response; the meme "don't burden me with the facts, my minds made up" might not have been originated for you but damn if it doesn't suit you.

From: ohiohunter
02-Aug-20
Please do, thank you for your commitment to my education. While you’re at it please explain to the tune master vertical dispersion, his knowledge of archery ballistics seems to be impaired.

From: spike78
02-Aug-20
The lighter faster arrows only penetrate better due to less surface area dragging in the gel or foam but when arrow meets bone I’m guessing the heavier and obviously thicker arrows are the key. That is why a 9mm will penetrate better in gel because narrower and faster then say a .45 slug but in real life on bone a .45 probably wins.

From: ohiohunter
02-Aug-20
Not probably, it will. 45’s hit like a mac truck, but are so slow you can see the bullet in flight at the right angle depending on lighting.

From: HDE
02-Aug-20
You guys touting Ashby's paper as the "gospel" truth on arrow dynamics relative to penetration need to understand the full measure of what is really happening.

He takes a High School senior physics course approach...

02-Aug-20
I just wonder this question on all of this discussion...Bull Elephant at 25 yards slightly quartering towards shot with a 75 lb bow. Do you want a 400 grain arrow or a 1,250 grain arrow?

From: ohiohunter
02-Aug-20
I’d stick with Ricardos formula and use about 800gr

From: Norseman
03-Aug-20
We’re listening...go on and enlighten us all

From: Jaquomo
03-Aug-20
Bull elk, moving through timber at an unknown distance and you have to stop him and shoot when he enters a shooting lane. You guess the lane to be somewhere between 40 and 60 yards but you only have about 10 seconds to process the opportunity and the timber confuses your depth perception. No chance to range him. Do you want a 400 grain arrow or a 1,250 grain arrow?

From: Grey Ghost
03-Aug-20
If I couldn't tell the difference between 40 and 60 yards, I think I'd hang up my bow. But I get what you are saying.

Yeah, HDE, please enlighten us.

Matt

From: Jaquomo
03-Aug-20
GG, a lot of eastern hunters have trouble judging distance on the ground out here in the West. I'm sure you saw it when you outfitted. I guess that was more of my point.

From: Norseman
03-Aug-20
Maybe the over draw bows will make a comeback?

From: Grey Ghost
03-Aug-20
Lou, yes I've seen it many times, and I agree with your point. Like you, I like a compromise between trajectory and penetration, for the sake of accuracy. There's few things as frustrating as missing an animal because you mis-judged by 5 yards. The memory of missing my Bighorn ram because of trajectory still haunts me after 17 years.

Matt

03-Aug-20
Well, I have never taken a shot past 25 yards that I haven't ranged or previously ranged a reference point, so it would be an easy choice for me. That bull elk lives for another stalk, but that's just my rule.

I'm not a super heavy arrow proponent, but to totally disregard that a heavy arrow will out penetrate a light arrow from the same setup... Levi made a comment that his sweet spot is a 500 grain arrow flying somewhere around 300 fps. Um yeah, that would be pretty nice, but my arms aren't that long!! Lol!

From: Jaquomo
03-Aug-20
From Levi Morgan's Field and Stream interview: "I shoot a 420-grain, 28-inch finished arrow for hunting"

03-Aug-20

DEMO-Bowhunter's embedded Photo
DEMO-Bowhunter's embedded Photo
I went back and looked at his post. I paraphrased it, but he said his "most efficient set up" I used sweet spot. Either way, he can produce some crazy speeds with a long draw

Funny that I shoot a 475 grain setup at 277 fps for almost all of my hunts because it is in the sweet spot for me. Decent weight and solid speed.

From: spike78
03-Aug-20
High FOC arrows are meant for when things don’t go right. I’m guessing Levi probably shoots well enough to put his mech where he wants it but some of us lesser folk may hit a shoulder from time to time.

From: bb
03-Aug-20
What could go wrong that a higher FOC will bail you out from? What is the FOC % where that happens?

From: Matt
03-Aug-20
bb, the % is more than you have but less than the % the FOC proponent has.

From: ohiohunter
03-Aug-20
Foc will bail you out about as much as being 1/256” from center shot or what mike n Matt Call out of tune..

From: Medicinemann
03-Aug-20
Ohiohunter, That bow was sent a couple years ago. If you haven't located modules for it by now, it is doubtful that you ever will. Remember, I shared the bow with you because I assumed that you preferred to hunt with higher poundages….as do I. I'd hate to see one of your friends hurt themselves for nothing but chest thumping purposes. Good luck....

From: Norseman
03-Aug-20
Is it easier to pull your arrow straight out of a target?

Or do some of you like to pull it out at an angle?

From: ohiohunter
03-Aug-20
I will hunt with it when and if I can get that DL shortened it’s a solid 2”+ too long. Doesn’t have to be perfect bc I’m confident I can use it with fingers which will give me some play room. For the time being on the rare occasion it’ll come out for an omg moment. Hopefully one of these days an ebayer will post an old cam, newer cams show up at times.

From: Mike in CT
03-Aug-20
"Foc will bail you out about as much as being 1/256” from center shot or what mike n Matt Call out of tune.."

Tell you what; pull up the post where either Matt or I have said that. Either that or admit you just made that up as part of the ongoing display of immaturity you've doled out.

Grow up.

From: ohiohunter
03-Aug-20
I'm just here waiting patiently for my lesson plan you promised. Did you help your pal with his terminology hang up? Not sure what stumped him, vertical or dispersion? The more you type, the more I smile. Cheers!

From: Mike in CT
03-Aug-20
No, you're continuing to parade your immaturity as if it should warrant a merit badge. You just made up a quote neither Matt or I ever made and can't man up and admit it (not that I expected you to).

Just provide a mailing address to ship your supply of binkies to Skippy......

From: ohiohunter
03-Aug-20
Now that’s a display of maturity ;)

From: Mike in CT
03-Aug-20
Just a target audience appropriate reply.....still earned as well....

From: Grey Ghost
03-Aug-20
Gee, we really got under James' thin skin, Mike.

For the record, James, I've heard the term used in bullet ballistics, but I've never heard anyone refer to arrow drop as "vertical dispersion". I guess it works, I just haven't heard it used that way.

So, why are you so defensive about the flawed test you posted? Is it because you shoot light arrows and REALLY wanted to believe the guy's penetration results were accurate? Sorry to disappoint you, James

And what "wrench" did you toss into the mix with this flawed test?

Matt

From: ohiohunter
03-Aug-20
I haven’t seen a self falating tag team like this for quite some time.

From: Mike in CT
03-Aug-20
James,

I don't doubt there's much you haven't seen, especially when it comes to comportment. (You can look that up along with flagellation in your spare time).

In an adult forum it's not often we're treated to outbursts such as yours; if you were maybe 13 or 14 I'd expect it, from a grown man it's kind of sad.

As if your petulance wasn't sufficient you had to start making s**t up; now that's really weak and compounded by your inability to simply own up to it and move on.

I'm starting to wonder if I should just chalk it up to the proverbial "silver spoon in the mouth" upbringing; perhaps you've gotten so accustomed to your flock lining up to kiss your ass that you're shocked when the rest of the world actually expects you to earn any level of respect.

Who knows, you may go on to something truly great one day; for now you'd be well-served by some introspection and the resultant self-improvement that should foster.

From: Jaquomo
03-Aug-20
Would you guys hold up for a bit? I need to run to the store for more beer and popcorn and don't want to miss anything!

From: ohiohunter
03-Aug-20
:-)

From: TEmbry
03-Aug-20
Mike,

I’m not here to step into a good pissing match. I would like to clarify my earlier post. I guess what I’m stating is, no one who understands the physics would argue the point that a heavier arrow will penetrate further. My point was more to the diminishing returns when it comes to increasing arrow weight. There is a balance between arrow drop and penetration concerns that everyone has to weigh (otherwise we’d all shoot 1000 grain arrows). For spot and stalk mountain hunters, gaining back some of that arrow drop for something misranged by a yard or two can be extremely helpful (especially if the two arrows being compared both have adequate penetration to begin with).

From: ohiohunter
03-Aug-20
Ya see, now you’ve gone and hyperbolized my hyperbolized statement bc your feelers are hurt. I’ve moved on long ago, you not so much. I see your knee pads are getting worn and matt is spent, I think you boys need a nap.

Tembry, I thought your intentions from your original post were quite clear.

Grab a chair the beer is frosty and the popcorn is buttery!

From: Grey Ghost
03-Aug-20
Is this guy 13 years old, or does he just act that way?

James, when the hole gets too deep, stop digging. You, my friend, are the one who keeps taking childish cheap shots at Mike and me for simply pointing out the flawed results of the test you posted. Own it, or keep losing the respect of others here. I don't really care. One thing is certain, I won't rush to click on another one of your threads until you grow up.

Matt

From: Mike in CT
03-Aug-20
Tembry,

Thanks for taking the time to clarify your earlier post; agree completely that there is a point of diminishing returns on arrow weight. I suspect we'd both be on the same page as well when it comes to the terminal end of the arrow being dictated by what that trade off (weight vs velocity) is.

From: Norseman
04-Aug-20
Is it easier to pull your arrow straight out of a target?

Or do some of you like to pull it out at an angle?

From: ohiohunter
04-Aug-20
ok ok, bear with me as I am not the phonics ninja like mike nor am I a tuning wizard. These guys may not be so bad after all, no ill will but really, you kids need to settle down. In the mess above this was said "at any moment an arrow can tear a clean hole". I cannot say I've been lucky enough to consistently get bullet holes from an obviously fishtailing arrow, but then again I haven't tuned 1000's of bows either. The former statement implies the arrow is constantly changing, which it is. How can something randomly oscillating be truly "tuned" in the sense to predict its motion in 3 planes 100%? (never mind all the other variables) Watch a high speed arrow launch video. We can somewhat predict z and y axis, but not the x axis. At launch and impact the x axis is very much in play regardless of tune. We'll act like we're in a vacuum and the archer is capable of maintaining an absolute perfectly level torque-less bow.

At what point does an arrow shaft fully recover from the acceleration pulse, or can someone look at stabilized arrows in flight and clearly identify the untuned arrow? Disclaimer (bc I know it'll come up): when I say untuned I am not suggesting a gross exaggeration where an arrow does a 90* tail whip, I am talking less than perfect. I believe at some point in flight tune will be unnoticeable, unmeasurable, and irrelevant. The perfectly tuned bow means nothing in the wrong hands, KS for example. His form would detract from taking full advantage of the most tuned bow in the world, not picking on KS as I am positive he will figure it out.

Yes, we all understand a tuned arrow is more efficient but where is that efficiency seen? Velocity? Trajectory? Slugs? KE? What impact does it have on the overall?.. perhaps accuracy? What quantifies a perfectly tuned arrow and will it make the avg archer measurably more accurate? If I shoot gel with one tuned arrow then move my rest out of spec 1/8", which is quite a bit by most standards, then shoot an identical arrow will the difference be significant? I speculate no, I could be wrong. If I had ballistic gel I'd do it, but its been so hot by the second shot I'd have a puddle.

Arrows are not lasers, arrows are largely imperfect as is the archer and bow, arrows rarely utilize all of their energy by entering a target perfectly perpendicular, especially animals. A perfectly tuned arrow will be more efficient at launch than its less than perfect friend, but how evident is this downrange? Remember this projectile is being launched by an upright man with an extended arm from a 2-4 limbed bow with a string that stretches and slams into a single off center rubber stopper along w/ a cable guard inducing unequal stress on said limbs, what could possibly go wrong? How can you take such a dynamic imperfect system and make it perfect? I can't.

From: Grey Ghost
04-Aug-20
This juvenile is a piece of work. The benefits of proper tuning has been demonstrated by countless archers who have forgotten more than James will ever know about archery. Yet he still yells “f tuning...look at my Facebook expert’s test”. Too funny.

Matt.

From: WapitiBob
05-Aug-20

All he did was shoot heavier/higher foc arrows showing the associated drop at distance after some chuckleheads said heavier slower arrows hit higher at 50 than lighter faster arrows. The ballistic jell shows both his and his wifes arrows and was just for chits and giggles, wasn't trying to show or prove anything other than they were getting enough penetration for Deer and as such, never re-tuned for the different shaft weights.

From: HDE
05-Aug-20
Atmospheric conditions alone can have a 3" difference in drop between real world conditions and an internet simulator calculator...

From: Grey Ghost
05-Aug-20
Can you elaborate, HDE? I'm always open to learning something.

Matt

From: WapitiBob
05-Aug-20
Couldn't tell you about some calculator but there is a 2" difference at 60 yards from my house in Bend and cascadians range west of Eugene. We see the same difference between here and Redding.

From: Grey Ghost
05-Aug-20
Now that you mention it, Bob, I've notice similar differences with large elevation changes. So, I guess air density is another part of the equation. The math involved to figure out that variable is above my pay scale, though.

So, I will retract my earlier comments about the 3" disparity. Which raises another question in my mind. Do the companies who provide yardage tapes for adjustable sights, based on the ballistic information you provide, account for elevation and different air densities? I'm guessing they don't.

Matt

From: HDE
05-Aug-20
Atmospheric conditions: humidity, wind (head or tail), elevation, temperature.

These, among others, are why Ashby presented the same kind of homework problem we did in high school physics. As a rule of thumb, heavier hits harder as long as variables are minimized. FOC, neutral axis of rotation, and triaxial forces can change that...

From: WapitiBob
05-Aug-20
GG, they create a "ballistics curve" with sight length, peep height, and 2 distances. The old original Archers Advantage used to create that curve using 4 distances but he decided 2 points was good enough. In practice, many see their mid yardage off by a few inches so we end up fudging arrow weight and/or peep height. For real short shots, 3-5 yards, the calculators are almost always off so we use the peep height to bring those in as that input doesn't affect the mid distances nearly as much as the real short ones. You can also input a chrono speed instead of shooting 2 marks but I don't know anybody that does that; shooting marks is a better way to go.

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