Who has snorted the Fairy Dust?

[waltholmes5]

I run a 3 pin sight, 3rd pin is a floater so I can practice at elk range for the day I finally get it together and head west in September. I keep them set at 20, 30, 40 for most of the season with the gaps being very consistent between them. 70# bow, 29.5" draw, 310 IBO with a 650 TAW, not sure what actual speed is

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Was just listening to a THP podcast (#167) that had Ranch Fairy and "Rocket man" on it. It was very interesting when they started talking about kinetic energy and compound bows, they describe compounds as a kinetic energy machine and in their testing bows consistently had a set kinetic energy. KE = M(mass) x V² (velocity squared) and once you calculated the Kinetic energy with 1 mass arrow and it's velocity you could extrapolate the velocity for any arrow mass because the kinetic energy was fairly constant.

(Adding with an edit) they also had a ton to say about kinetic energy and momentum on light vs heavy at distance AND a separate statement in favor of high FOC regardless of weight

 

[Allegheny Tom]

Not sure If I found Ranch Fairy first or the Ashby reports. As things worked out I found both & for the most part Troy's videos are primarily based on his accurate takeaway's from the Ashby reports. So, while the the tongue in cheek question could have been presented differently, my takeaway of the question is, have we tried the Ashby principals that Troy is attempting to promote?

If that is the question, then yes I have. Though most of my archery whitetail deer hunting has been done with a 450 grain to 500 grain total arrow weight and I had acceptable results with the mid weight arrow tipped with both fixed blades & expandable broad-heads over the last 35 years. More often than not the broad-heads were 125 grains.
Last fall, most likely due to troys YT videos I opted to try a heavier arrow & one of those little 1 1/8" cut diameter single-bevel Broad-heads & try a tapered arrow for the sake of experimentation. That sample of one did not disappoint. Only took one archery deer last fall with the 650 grain arrow. Truth be told my old set up would have most likely worked as well as the plan B arrow.

What was different with last years deer was the deer was only lightly startled at the shot. Shot ended up being a bit high and back. Deer bound off for 15 yards walked another 20 yards & tipped over. Distance traveled after the shot was defiantly less than average. In that case the 1.125" diameter cut single bevel worked flawlessly. I look forward to experimenting more with this setup. I hope to take two deer next fall with the same or a similar set up.

Troy is part of the staff at the Ashby Bowhunting Foundation.

 

[Horn]

Any of you guys try GT force f.o.c. arrows? I bought a 6 pack, worried about how thin walled they are but they come with an aluminum insert and a 100gr brass insert.

 

[Iron_llama]

Any of you guys try GT force f.o.c. arrows? I bought a 6 pack, worried about how thin walled they are but they come with an aluminum insert and a 100gr brass insert.

Check out Ethics Archery components, wide variety of inserts and halfouts and collars and sleeves and such. Everything you need to add weight and durability to the pointy end of your arrows.

 

[Horn]

Check out Ethics Archery components, wide variety of inserts and halfouts and collars and sleeves and such. Everything you need to add weight and durability to the pointy end of your arrows.

I played with calculators quite a bit looking at options to try. Brass and aluminum aren't my first choices for inserts but the 12.3 or and the 100 give me quite a lot of room on total weight and FOC

 

[BowhunterXC]

Any of you guys try GT force f.o.c. arrows? I bought a 6 pack, worried about how thin walled they are but they come with an aluminum insert and a 100gr brass insert.

I wasn't aware of Gold Tip making an arrow that is specifically for high F.O.C. Just looked them up and noticed that 400 spine shafts are 8.8 gpi, whereas Hunter XT or Traditional XT shafts are 9.3 gpi, in the same spine.

I've been using Hunter XT 300 spine for my Elite Ritual compound, which is 57# at 29" DL. I have a 100 gr. brass insert, 150 gr. tip weight and 3" Rayzr feathers on a 29" arrow, which gives me a 520 TAW and 20.5% F.O.C. This setup gives me excellent arrow flight and most importantly, I got pass-thru shots on all the deer that I shot this past fall.

I'm in the process of building a similar arrow for my 19" Hoyt Satori riser with Uukha Gobi short limbs, which is 44.2# at my 28" DL. According to the Dynamic Spine Calculator on 3 Rivers Archery website , looks like I'll be shooting a 400 spine Gold Tip Traditional shaft with 12 gr. aluminum inserts, 150 gr. tip weight, 3 4" feathers and a 30" shaft length. Again, I'm in the process of building it, but their calculator says it'll have a 13.8% F.O.C.

 

[Horn]

I wasn't aware of Gold Tip making an arrow that is specifically for high F.O.C. Just looked them up and noticed that 400 spine shafts are 8.8 gpi, whereas Hunter XT or Traditional XT shafts are 9.3 gpi, in the same spine.

I've been using Hunter XT 300 spine for my Elite Ritual compound, which is 57# at 29" DL. I have a 100 gr. brass insert, 150 gr. tip weight and 3" Rayzr feathers on a 29" arrow, which gives me a 520 TAW and 20.5% F.O.C. This setup gives me excellent arrow flight and most importantly, I got pass-thru shots on all the deer that I shot this past fall.

I'm in the process of building a similar arrow for my 19" Hoyt Satori riser with Uukha Gobi short limbs, which is 44.2# at my 28" DL. According to the Dynamic Spine Calculator on 3 Rivers Archery website , looks like I'll be shooting a 400 spine Gold Tip Traditional shaft with 12 gr. aluminum inserts, 150 gr. tip weight, 3 4" feathers and a 30" shaft length. Again, I'm in the process of building it, but their calculator says it'll have a 13.8% F.O.C.

The black label quantum and , I think, airstrikes are a little lighter at 300 spine ( both .204 i think, force/hunters are .245), victory has some offerings as well.

If you're looking at hunters the price is the same for .001 straight but you get both inserts. Those feathers really bump that FOC up too! Good find!!

Also glad to hear what you're shooting, I put the force arrows in archers advantage and it says I'll need to be pulling 70# with 225 up front. Which I can do 70# but I'm not sure that's where I want to be. Definitely want "perfect arrow flight"

 

[BowhunterXC]

Also glad to hear what you're shooting, I put the force arrows in archers advantage and it says I'll need to be pulling 70# with 225 up front. Which I can do 70# but I'm not sure that's where I want to be. Definitely want "perfect arrow flight"

@Horn
Do as you please, but I've witnessed far too many rotor cuff surgeries to be shooting high poundage draw weight. I dropped from 72# down to the mid 50s, when I was in my early 40s. I'm 65 now and wouldn't dream of going back up in draw weight, even though I'm in good shape and quite capable. I want to continue to enjoy archery and not have to switch to a crossbow, IF I can avoid it.
I'm with you 100% on the perfect arrow flight! A well tuned bow, combined with a good arrow weight/balance, is hard to beat.
The THP guys mention a woman shooting 24" DL out of a 40# bow and she kills an Eland with full penetration. Very impressive!
At the 9 minute mark. The entire video is full of good information.

 

[NMSbowhunter]

@Horn
Do as you please, but I've witnessed far too many rotor cuff surgeries to be shooting high poundage draw weight. I dropped from 72# down to the mid 50s, when I was in my early 40s. I'm 65 now and wouldn't dream of going back up in draw weight, even though I'm in good shape and quite capable. I want to continue to enjoy archery and not have to switch to a crossbow, IF I can avoid it.
I'm with you 100% on the perfect arrow flight! A well tuned bow, combined with a good arrow weight/balance, is hard to beat.
The THP guys mention a woman shooting 24" DL out of a 40# bow and she kills an Eland with full penetration. Very impressive!
At the 9 minute mark. The entire video is full of good information.

The story of the lady killing the nilgai with a 43# bow is in Jeremy Johnson's book Can't Lose Bowhunting.

 

[Weldabeast]

Repost....

 

[Horn]

@Horn
Do as you please, but I've witnessed far too many rotor cuff surgeries to be shooting high poundage draw weight. I dropped from 72# down to the mid 50s, when I was in my early 40s. I'm 65 now and wouldn't dream of going back up in draw weight, even though I'm in good shape and quite capable. I want to continue to enjoy archery and not have to switch to a crossbow, IF I can avoid it.
I'm with you 100% on the perfect arrow flight! A well tuned bow, combined with a good arrow weight/balance, is hard to beat.
The THP guys mention a woman shooting 24" DL out of a 40# bow and she kills an Eland with full penetration. Very impressive!
At the 9 minute mark. The entire video is full of good information.

I appreciate your advice, I'll probably be limited to about 58lbs minimum. I was shooting 62 last year. I think my other bow will go down to 50 but I don't plan on using that one. As a side note I sure wish there were more 65 pound bows, 55-65 seems ideal to me.

We'll see how they tune, if I can drop down the poundage I will, or maybe switch to a 340 spine instead of 300. I've got some 340 spine with 75 gr inserts too so once the weather is nicer and the days longer I'll do more tinkering

 

[Horn]

I put a BG dual track on my new bow, maybe the slider will help with my trajectory concerns, not that I plan on shooting past 30 at deer

 

[BowhunterXC]

The story of the lady killing the nilgai with a 43# bow is in Jeremy Johnson's book Can't Lose Bowhunting.

I own that book. Good reading!

 

[waltholmes5]

Oof, thread slowed down. How was everyone's season? Making any changes in the off-season?

 

[Horn]

Deer season is a wrap here. Looking forward to turkey.

But about the fairy dust, anyone study the Barnette arrow flight paper? Interesting read if you haven't checked it out

Supplemental Research — Ashby Bowhunting Foundation

Other professionals have jumped in and supported the work of the foundation through their own research. We are grateful for their efforts and willingness to share it with us and other bowhunters.

www.ashbybowhunting.org

Titled " Engineering Insights On Archery"

Looking to discuss page 47

 

[Plebe]

Was just listening to a THP podcast (#167) that had Ranch Fairy and "Rocket man" on it. It was very interesting when they started talking about kinetic energy and compound bows, they describe compounds as a kinetic energy machine and in their testing bows consistently had a set kinetic energy. KE = M(mass) x V² (velocity squared) and once you calculated the Kinetic energy with 1 mass arrow and it's velocity you could extrapolate the velocity for any arrow mass because the kinetic energy was fairly constant.

(Adding with an edit) they also had a ton to say about kinetic energy and momentum on light vs heavy at distance AND a separate statement in favor of high FOC regardless of weight

So, for a given constant taw (mass), increasing draw weight doesn’t produce more velocity and therefore more KE?

 

[Horn]

Sounds like the paper I just posted about is the same/related to the THP podcast.

Sorry, I didn't think to look back at posts. I thought I was keeping up

 

[kyler1945]

So, for a given constant taw (mass), increasing draw weight doesn’t produce more velocity and therefore more KE?

“The bow” is “the specific model bow set at a certain draw weight and length”. Increasing weight or length will increase KE output . The point they, and Ashby are making, is that the bow is the energy generator - not the arrow. So changes to the arrow don’t change the amount of energy transferred into it when it’s shot.

 

[krub6b]

“The bow” is “the specific model bow set at a certain draw weight and length”. Increasing weight or length will increase KE output . The point they, and Ashby are making, is that the bow is the energy generator - not the arrow. So changes to the arrow don’t change the amount of energy transferred into it when it’s shot.

Technically the bow isn't an energy generator, it's a storage device that holds the energy you put into it and then transfers that to the arrow. The valid part of page 47 is that at a set weight and draw length, these would be your comfortable max weight and draw length, energy is the same as it leaves the string, no matter what arrow you shoot, as soon as that arrow leaves the bow though the arrow does what arrows do which is slow down and loose energy, how much it loses is directly related to the arrow mass

 

[Plebe]

Technically the bow isn't an energy generator, it's a storage device that holds the energy you put into it and then transfers that to the arrow. The valid part of page 47 is that at a set weight and draw length, these would be your comfortable max weight and draw length, energy is the same as it leaves the string, no matter what arrow you shoot, as soon as that arrow leaves the bow though the arrow does what arrows do which is slow down and loose energy, how much it loses is directly related to the arrow mass

I kind of think a bow is a machine. When drawn it has an energy potential. When released, it does work, converting that potential to KE and energy loss (vibration and noise). Something like that.

Depending on what an arrow encounters before coming to rest, it’s slowing down is related to it’s mass and it’s velocity. The proportionality of how those factors resist slowing down forces depend on the slowing down forces. There’s the rub. Anyway, that’s where I’m at with the physics.

Yeah, pick up a bow and draw an arrow and you have introduced a specific PE in the system. Release and it will exert on the arrow a specific force and give it a specific KE. Arrow mass and velocity are proportional to that specific KE. Indeed. I just wanted to flush out that most bows don’t have a set KE as seemed the inference. We set them to a specific potential.