Would You Sacrifice Speed for a Slight Bump in Kinetic Energy?

[jstanton007]

They bend, giving you issues with BH flight.


I'm still thinking something off with the speeds, KE wouldn't change that much, and the speed should be pretty linear in that range of 3grs/fps. Or a little off on weights.

Do you prefer the HIT inserts on the Easton's or the Shok TL204 inserts on the Victory's? Or should we be looking at something else?

 

[SDHNTR]

Using the calculator at N1 Outdoors, it looks like the RIP at 271fps and 422gr should give me about 0.507 slugs of momentum while the Axis at 258fps and 476gr would give me 0.545 slugs of momentum. I'm not sure what the scale is on momentum and if this is a significant difference?

Not a huge difference.

Another element you may not be considering and that won’t show up in calculations, is a heavier arrow is quieter. It’s impossible to make an arrow fly faster than the speed of sound so if an animal hears the bow go off and reacts you are wasting time to think you can get an arrow fast enough to beat the reaction. Instead, seek a quiet arrow, so the animal is less likely to react. I like heavier, to a point. I’ve found the sweet spot to be 450-475 gr ish.

 

[Billy Goat]

Do you prefer the HIT inserts on the Easton's or the Shok TL204 inserts on the Victory's? Or should we be looking at something else?

Hit inserts, the victory inserts I haven't bothered to use. I has issues years ago with SS halfout's bending and scraped the idea of using any of them.


I think your hunting arrow comes down to how you practice. An issue I have had several times is getting an arrow to the intended target. Besides indoor, I'm usually shooting a minimum of 280 fps, it's what I know. I dabled in a heavier arrow setup that took me into the upper 250's, guess what, still mostly didn't have a bit of issue blowing through an animal, except a coyote, a coyote stopped an arrow. I did have a few instances of hitting obstacles on the way to the target, stuff that I wasn't use to paying attention to was in the flight path. That's a me problem, not an arrow problem, but I'm just use to a certain flight path and I haven't found a reason to switch.


390-425 gr is where I'd personally be for elk at those specs. Making sure I had a well tuned bow, and a good broadhead. That's coming from I really don't know how many deer and 9 dead elk personally and up into the 30's I've been a part of. Possibly a small number, but the biggest factor in killing elk has been shot placement, not poundage of the bow or how heavy the arrow was. Even halfouts that bent going through an animal and created an arc still killed fine.

 

[Mighty Mouse]

@Mighty Mouse @Billy Goat
I guess the better question, looking at momentum now, is which arrow setup would you lean toward assuming both are equally accurate? Also would the RIP benefit from a 125gr head up from bumping the arrow weight up to 447? I will need to chrono this configuration though to get a speed.

Any of the arrow weights you've mentioned in this thread will work fine. You won't see a major difference between them in practice from the lightest (422 gr) to the heaviest (476 gr).

Arrow speed vs. weight is a trade-off between the flatter trajectory and tighter pin gaps of a lighter/faster arrow vs. greater penetration potential of a heavier/slower arrow. Where along the spectrum you choose to land is largely personal preference based on a combination of factors such as max shot distance, hunting style, and the animal you're hunting. There's no "correct" arrow weight, just a wide range of options bounded on the low end by avoiding damage to the bow (minimum 5 gpp). "Too heavy" is wherever you decide your max range has become too short and/or pin gaps have become too large.

That said, 7 gpp (grains of arrow weight per pound of draw weight) generally provides a good balance of weight and speed for a hunting arrow IMO. 7 gpp at 65# would be 455 gr.

Now that you have KE data for your buddy's bow, you can estimate speed at any arrow weight with a high degree of accuracy. Assume KE remains constant and use KE to calculate speed:

Arrow Speed in fps = SQRT(450,380 × KE in ft-lbs ÷ Arrow Weight in gr)​

​

Example using the average of your two KE data points (69.6 ft-lbs) to calculate speed at 447 gr:

SQRT(450,380 × 69.6 ft-lbs ÷ 447 gr) = 265 fps​

​

If your buddy is planning to use these arrows for western archery this year, y'all need to get off the fence soon so you have time to practice with the arrows and ensure the bow is tuned to shoot them well. Time spent shooting and tuning is much more beneficial than laboring over arrow builds.

 

[roadrunner]

Simply put; KE of the arrow is the work the bow did to send the arrow of a certain mass downrange at whatever velocity at the bow riser.

Mass is the independent variable.
Velocity is the dependent variable.

KE is the area under the momentum curve, or 1st order integral.

This is why it doesn't matter. It has nothing to do with dispatching an animal.

 

[Zac]

@Mighty Mouse @Billy Goat
I guess the better question, looking at momentum now, is which arrow setup would you lean toward assuming both are equally accurate? Also would the RIP benefit from a 125gr head up from bumping the arrow weight up to 447? I will need to chrono this configuration though to get a speed.

This is not a question you should have to ask. Your problem is that you are assuming. If you went out and group tested both options, shot broadheads with both options, shot unknown yardage with both options you would have your answer. And it wouldn’t have anything to do with KE. Sometimes you have to pry your ass off the computer and go shoot your bow.

 

[5MilesBack]

Do you prefer the HIT inserts on the Easton's or the Shok TL204 inserts on the Victory's?

HIT's without any doubts. I've been using HIT's in all my .204" arrows for the past 17 years.

 

[wesfromky]

Bill at Iron Will did a few short youtube videos on the science of bowhunting. Worth checking out. For me, the one takeaway that seems to get lost in a lot of these types of threads is just how important having a super sharp, cut on contact head is with regards to penetration. He goes into that in one of those videos, worth checking out.

 

[Zac]

 

[CowboyD]

Short answer is no. I prefer speed.

 

[KHNC]

I guess so, i am trying it this year. Went from 425gr to 479gr and 125gr heads. My garmin Xero will shoot out to 87 though. Didnt really lose much of anything from what i can tell.

 

[wapitibob]

A very good video that most will ignore. People don't want the truth, they want the shortcut magic.

 

[Bump79]

Accuracy first, always.
Then momentum, to carry the arrow through after impact.
Then speed.
Never KE.

I'd switch this around.

Accuracy first
Structural integrity
Speed
KE & M are a byproduct of getting the above right. FOC fits in that same category.

Speed is not irrelevant. It provides range forgiveness which for any mobile style of hunting needs to be high up on the list. Speed also provides less time in flight and therefore less animal movement.

@jstanton007 get as close to 280 fps without sacrificing durability or arrow flight.

 

[SDHNTR]

Speed also provides less time in flight and therefore less animal movement.

Matters not if the animal hears the bow go off.

 

[Bump79]

Matters not if the animal hears the bow go off.

This doesn't jive. So if the animal hears then bow go off - then has less time to react - your theory is that it doesn't move more?

That's just how speed works. You drive the same distance faster - you get there in less time.

Let's use his setup as an example. If the animal votes to move. It can move up to 2.5" inches more and if it takes off like an Olympic sprinter - it's moved your arrow 1.4" further back.






It all cumulates in something like this. If the animal dips away from the arrow it's like a boxer taking a punch. It soaks up the KE & M. At the end of the day it's a wash in KE and the gain in momentum isn't all that great. For a sizable loss in trajectory while increasing the odds of not hitting where you meant.

 

[SDHNTR]

This doesn't jive. So if the animal hears then bow go off - then has less time to react - your theory is that it doesn't move more?

That's just how speed works. You drive the same distance faster - you get there in less time.

Let's use his setup as an example. If the animal votes to move. It can move up to 2.5" inches more and if it takes off like an Olympic sprinter - it's moved your arrow 1.4" further back.
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It all cumulates in something like this. If the animal dips away from the arrow it's like a boxer taking a punch. It soaks up the KE & M. At the end of the day it's a wash in KE and the gain in momentum isn't all that great. For a sizable loss in trajectory while increasing the odds of not hitting where you meant.
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My goodness. I don’t even know what all that is supposed to mean. You are overanalyzing. A lighter arrow is a louder arrow. Fact. An arrow will never be able to be shot out of a bow faster than the speed of sound. Fact. So your efforts to increase speed in an attempt to outrun an animal’s reaction to sound are mostly a waste of time. Your efforts are better spent making your bow quieter, which may include a heavier arrow. That’s it. You don’t need mental masturbation to understand the principal.

 

[Billy Goat]

My goodness. I don’t even know what all that is supposed to mean. You are overanalyzing. A lighter arrow is a louder arrow. Fact. An arrow will never be able to be shot out of a bow faster than the speed of sound. Fact. So your efforts to increase speed in an attempt to outrun an animal’s reaction to sound are mostly a waste of time. Your efforts are better spent making your bow quieter, which may include a heavier arrow. That’s it. You don’t need mental masturbation to understand the principal.

Why is a lighter arrow a louder arrow?



It might make the bow slightly louder, but it's not necessary louder.



I'm pretty convinced bow noise has little to do with animal reaction unless it was alerted by you drawing and is focused on you. At that point, it's hard to know if it's sight or sound they are reacting to.


A loud arrow in the air, they definitely react to, if it's coming their direction.

 

[waldo9190]

My personal rule of thumb is shooting as heavy of an arrow I can while maintaining 280-ish FPS. Seems like a good balance of arrow weight and pin gap/trajectory.

Don't over think it.

 

[Beendare]

I used to shoot for Oneida. Many of the young guys will not know these bows....but talk about a string jumping machine- those were it.

It thought me just what SD is trying to point out.....a sharp unnatural slap when your bow goes off will get a reaction from many animals if there isn't much environmental noise like wind or leaves rustling.

I've had it happen on one of those dead silent mornings in the woods with my recurve on Coues deer.... which is pretty darn quiet. Those Coues and Axis deer bring string jumping to a new level.

It's a worthy exercise to experiment with different weight arrows....so retimes it makes a difference. Going from a sharp slap to a low thump can be the difference with these critters, IME.

I had 3 different arrows tuned to my 55# recurve- 380g,435g,and 500g- with the 380 sounding like a compound going off. The 435 was significantly quieter.

I was playing with different arrows in my PSE Levitate- but I have to go up 100g+ to make any difference in decreasing the sound.

 

[flyboy214]

Here are my experiences with different weight arrows and insert systems.

5 deer taken with various arrow weights. I only draw 28 inches at 60 lbs and shoot a Mathews V3. The broadheads used for these deer were all magnus cut on contact style with a mix of buzzcut and stingers.

Cheap and simple Gold tip hunter XT 425 grains.
- Deer one full pass through 59 yards, entered in front of the hip and exited rib cage on the other side.
- Second deer with the 425 grain arrow I shot tight to the shoulder and the arrow exited the ball joint in the leg and caught at the fletchings. That is the only non-passthrough I have personally had.
-with the basic aluminum inserts, some of them did not spin true after a full season

Second arrow setup was victory VAP with steel outserts. 435 grains
-I didn't kill a deer with these, but after a full season, most of them did not spin true with a broadhead. I chalk that up to the thin shaft of the insert bending under repeated impacts.

Third arrows Setup Sirius Apollos 495 grains with steel ethics outserts
- First deer with these was a basic quartering away shot where the arrow took out a few ribs and stuck in the ground on the other side.
- Second deer with that setup was a bigger buck. He jumped the string and did a drop and roll. The arrow took him through both shoulders and stuck in the ground. I watched him fall.

Fourth setup Sirius apollos 460 grains with iron will hit insert and collar. (same dozen from before. I have yet to break one)
- Doe shot at 47 yards broadside. The arrow zipped through and she piled up after a 90 yard dash.

My conclusions are that 5mm arrows with HIT inserts and collars are probably the best balance of durability and a smaller diameter shaft for reduced drag. Standard diameter arrows with normal inserts and 125 grain heads work fine, but the aluminum inserts can bend over time, resulting in an arrow that doesn't spin true with a broadhead. It was interesting that the 425 grain setup passed through after literally splitting the thickest part of a deer's humerus bone. My slowest setup was 256 fps and the fastest was 282 fps. Speed seemed to have minimal effect on the terminal performance, but those heavy apollos are stupid quiet.

I think either of your arrow builds will work fine. Maybe avoid a massive mechanical broadhead with the lighter arrow setups.