Arrow help for short draw length and 70lbs draw

[Uno]

Good Morning y'all. I could use a little help digging myself out of the rabbit trail that I have dove into. I have scoured this site and the web trying to wrap my mind around arrow KE, Momentum, and FOC for short draw lengths with 70lbs draw weights. Most of what I have found pertains to short draw, and low poundage draw weights, which may or may not apply. I have spoken to guys at the local club, and I am getting polar opposite responses. The Trad guys swear by heavyweight arrows, and the Compound guys all say lightweight and fast. None of them are handicapped at 5'4" with a 25" draw. To keep from rambling, I have my first elk hunt in September, and I am trying to find the happy medium between penetration and arrow flight, with a goal to have a range of 50 yards. My current whitetail setups are below, with a third, the VAP RIP's, I have been contemplating for elk; whichever I go with will have a 100gr COC broadhead on the business end. Thank Y'all for the help and the clarity.

Easton FMJ
Spine - 350
Insert - Standard
Weight - 451gr
Speed - 246FPS
FOC - 7.5 %
KE - 60.62
Momentum - .493


Gold Tip Valkury
Spine - 340
Insert - 50gr
Weight - 399.2 gr
Speed - 265 FPS
FOC - 13%
KE - 62.21
Momentum - .469

VAP RIP
Spin - 300
Insert - 75gr
Weight - 433.8
Speed - 255' ish
FOC - 15%
KE - 62.51
Momentum - .49

 

[Samdemarais]

Good Morning y'all. I could use a little help digging myself out of the rabbit trail that I have dove into. I have scoured this site and the web trying to wrap my mind around arrow KE, Momentum, and FOC for short draw lengths with 70lbs draw weights. Most of what I have found pertains to short draw, and low poundage draw weights, which may or may not apply. I have spoken to guys at the local club, and I am getting polar opposite responses. The Trad guys swear by heavyweight arrows, and the Compound guys all say lightweight and fast. None of them are handicapped at 5'4" with a 25" draw. To keep from rambling, I have my first elk hunt in September, and I am trying to find the happy medium between penetration and arrow flight, with a goal to have a range of 50 yards. My current whitetail setups are below, with a third, the VAP RIP's, I have been contemplating for elk; whichever I go with will have a 100gr COC broadhead on the business end. Thank Y'all for the help and the clarity.

Easton FMJ
Spine - 350
Insert - Standard
Weight - 451gr
Speed - 246FPS
FOC - 7.5 %
KE - 60.62
Momentum - .493


Gold Tip Valkury
Spine - 340
Insert - 50gr
Weight - 399.2 gr
Speed - 265 FPS
FOC - 13%
KE - 62.21
Momentum - .469

VAP RIP
Spin - 300
Insert - 75gr
Weight - 433.8
Speed - 255' ish
FOC - 15%
KE - 62.51
Momentum - .49

I wouldn’t over think it. Stay between 265 fps-280 and make sure you shoot a high quality sharp broadhead. Probably a 2 blade with bleeders for best penetration. A perfectly flying arrow will penetrate best so focus on tune and shooting. I would go with a 400 grain arrow and 12-15% FOC. If you shoot those 246 FPS logs your trajectory will be rainbows at 50 and could cost you some shot opportunities.

 

[Mighty Mouse]

Are these speeds measured (with the same chronograph at the same lighting conditions) or calculated? KE tends to increase (slightly) with increasing arrow weight, so it's surprising that you're showing a decrease in KE from 434 to 451 gr. KE is just a number though and shouldn't be your deciding factor, just wanted to point out an oddity in the data that might mislead you away from a heavier arrow.

Speed gives you a flatter trajectory and arrow weight gives you better penetration potential. Where along the spectrum is right for you is entirely personal. Test out different arrow weights and see how heavy you can go while maintaining a trajectory you're comfortable with out to your desired max range. Whatever arrow weight you settle on, I'd recommend putting a razor sharp 2-blade fixed head on it to maximize penetration potential.

 

[Beendare]

You are obviously using a calculator OP because those numbers are incorrect.

Best advice is to use a very efficient Brodhead on a lower energy set up.

Arrow weight is a trade off but in your case I would err on the side of a little bit more arrow weight

Make sure you assemble your arrows perfectly straight and that you Broadhead tune your bow..... and you will be fine
....

 

[Uno]

I appreciate the reply's and I am probable over thinking it to the N'th degree.

The speeds for the Gold Tip and FMJ were measured out of the same chronograph on the same trip to a shop. The KE calculation surprised me as well; I used the real tree and Gold tip calculators to figure out the Momentum and KE numbers.

I was looking at a three-blade VPA, but I am open to a two-blade. Is the penetration difference substantial? I have never shot a two-blade, always opted for 3 and 4 blades for whitetail, all be it an elk is a much larger animal.

 

[Mighty Mouse]

I was looking at a three-blade VPA, but I am open to a two-blade. Is the penetration difference substantial? I have never shot a two-blade, always opted for 3 and 4 blades for whitetail, all be it an elk is a much larger animal.

Below is a link to the best comparison I've seen of broadhead penetration ability. The test results show a much lower force required for a fixed 2-blade head (Iron Will in this case) to penetrate compared to a fixed 3-blade or a mechanical. Real world penetration results on a live animal may or may not be as drastically different as the test results suggest, but I believe the general trend would hold true (i.e., fixed 2-blade will out-penetrate fixed 3 or 4-blade or any mechanical).

At 25" DL you're starting at a disadvantage and would be well served to use a 2-blade fixed head on as heavy an arrow as you can tolerate.

https://www.ironwilloutfitters.com/lab-and-field-testing/2020/6/18/broadhead-force-testing

 

[N2TRKYS]

I’d shoot a 3 blade and wouldn’t lose any sleep over it. Mine wouldn’t even be a coc broadhead, either. Oh, the horror.

 

[MattB]

I would aim for 425-450 grs.

 

[MADD BEAR]

Sounds like you need to practice shooting through your arrow options before jumping to any conclusions about final arrow choice.

Bows and arrows require a skill set and command to be proficient. Just having the optimal gear isnt going to make you a good hunter. Spend the time and shoot arrows with the purpose of tuning to make them better. Do not just huck arrows if you want to get better.

Do not think of a short draw as a handicap, you have the ability to kill an elk just the same as any other bowhunter. You will want to be true with yourself and your abilities and stick to that. If you know your arrows are not efficient at 40+ yards, don’t shoot past 40. Just accept those type of limitations on your hunts.

If it makes you feel better I shoot massive almost full length arrows because of my draw length and it requires me to do things a little different. Anything before 12 yards my arrow is still paradoxing and its just something I have to live with so my shots are all 15+ yards.

A shorter arrow actually flies better its like a crossbow bolt. So play around with what you have. You may end up just needing a heavier point on the front. With a lighter arrow a lot of energy from your 70# bow is being lost due to vibration. A heavier arrow can launch better and stabilize quicker.

Just my opinion. Good luck in the bush.


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[Uno]

Thank y’all for all the feedback. I’m looking at picking up the grizzly stick Over Kill Maasai to take with me now, and I will build the VAPs at 433grs to play with. Getting yalls feedback made me start comparing my arrow delima to working a load for a new rifle, and I need to spend some time at the range testing. Thanks again, and I hope y'all are all staying safe with this weather.