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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

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.

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!

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.

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

Matt

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

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

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.

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

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

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

“ 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.”

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

Matt

All the best,

Matt

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

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.

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.....

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.

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.

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.

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

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

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

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.

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

Yeah, HDE, please enlighten us.

Matt

Matt

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!

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.

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

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.

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

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

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.

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).

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

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.

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

Matt.

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.

Matt

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

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...