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Can anyone estimate what the kinetic energy of my hunting setup would be? Or is there a website that helps me understand the relationship between my kinetic energy and approximate kinetic energy's needed for different species?

I'm shooting a mathews drenalin set at 65 lbs with 28.5" draw length and Easton Axis ST 400s (blazer vanes) with 100 grain heads & lumenocks. I'm not real sure on the length of my arrows, I do know they stick out about an inch past my QAD rest.
 

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the two variables you need are arrow weight (in grains) and arrow speed ( in feet per second). after you have that you can figure it out. the gold tip website goldtip.com has a kinetic energy calculator on it. you just plug in the info above and it'll tell ya. i think the formula to figure it out is (arrow weight) divided by ( 450435 ) multiplied by (arrow speeed) multiplied by (arrow speed).
 

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sorry i forgot to answer your original question i would guess it to be in the neighborhood of 65 lbs of ke. plenty efficient for anything you'll encounter in this country. the reason i say this is i have a dxt(pretty much same bow but shorter). i'm pulling 60.6 lbs at 29inches with a 413 gr arrow( a 340 series beman) and i have 62 lbs of ke.
 

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Guessing with the numbers but here we go...
Drenny @65lb adn 28.5" draw
Axis ST at 29 with Blazers should put you close to 440-445 grain with the lumenocks.

Assuming you have a peep, brass nock and loop on it you should be looking at 275fps or so.

KE=71.82
FOC=10.2

Again...guesstimating but that should be within a few lbs KE wise at least.

They say 45-50lb of KE is all that's needed for most North American game but I wouldn't hunt Grizzlies with 50 myself;)

More important than KE is momentum IMO. A heavier arrow will have a lot more momentum and result in better penetration all else being equal.

Dangerous game in Africa requires 80lb of draw weight and a minimum of 1000 grain arrow weights. Now we're talking Cape Buf, Lions, Hippos and Giraffes here but that'll give you an indication.:D

I hear all the time "The indians killed buffalo with a stick and string...my arrows are fine"

True...but the indians weren't shooting space are carbon shafts that are measured in fractions of grams either:idea: They were using real wood and they were HEAVY and they penetrated even at 45-55lbs
 

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Scott- If you get a chance, fire an arrow through a chronograph and weight the arrow in grains. With those two measurements you can get as accurate as possible. With that said, Kelly's gonna be pretty darn close. And I agree with what he's said regarding weight and momentum. But truth be told, you'll have more than enough to get through any animal in North America.;)
 

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Guessing with the numbers but here we go...
Drenny @65lb adn 28.5" draw
Axis ST at 29 with Blazers should put you close to 440-445 grain with the lumenocks.

Assuming you have a peep, brass nock and loop on it you should be looking at 275fps or so.

KE=71.82
FOC=10.2

Again...guesstimating but that should be within a few lbs KE wise at least.

They say 45-50lb of KE is all that's needed for most North American game but I wouldn't hunt Grizzlies with 50 myself;)

More important than KE is momentum IMO. A heavier arrow will have a lot more momentum and result in better penetration all else being equal.

Dangerous game in Africa requires 80lb of draw weight and a minimum of 1000 grain arrow weights. Now we're talking Cape Buf, Lions, Hippos and Giraffes here but that'll give you an indication.:D

I hear all the time "The indians killed buffalo with a stick and string...my arrows are fine"

True...but the indians weren't shooting space are carbon shafts that are measured in fractions of grams either:idea: They were using real wood and they were HEAVY and they penetrated even at 45-55lbs


Well put.

after you get some numbers out of a chrono, try this also.

http://www.backcountrybowhunting.com/articles/tools.php
 

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chronograph graph would be the ticket. I have a bowtech gaurdian that is shooting a 275 fps with a 445 grain CX aramid arrow. I was surprised, although I am shooting a heavy arrow with a kisser, peep and cat wiskers. Head out to Vans and check out your FPS and Grains... They are good people!
 

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Guessing with the numbers but here we go...
Drenny @65lb adn 28.5" draw
Axis ST at 29 with Blazers should put you close to 440-445 grain with the lumenocks.

Assuming you have a peep, brass nock and loop on it you should be looking at 275fps or so.

KE=71.82
FOC=10.2

Again...guesstimating but that should be within a few lbs KE wise at least.

They say 45-50lb of KE is all that's needed for most North American game but I wouldn't hunt Grizzlies with 50 myself;)

More important than KE is momentum IMO. A heavier arrow will have a lot more momentum and result in better penetration all else being equal.

Dangerous game in Africa requires 80lb of draw weight and a minimum of 1000 grain arrow weights. Now we're talking Cape Buf, Lions, Hippos and Giraffes here but that'll give you an indication.:D

I hear all the time "The indians killed buffalo with a stick and string...my arrows are fine"

True...but the indians weren't shooting space are carbon shafts that are measured in fractions of grams either:idea: They were using real wood and they were HEAVY and they penetrated even at 45-55lbs
sounds close if he gets that speed! But do you really think that bow can push an 440 grn arrow 275? I was guessing more like 255-260.
 

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sounds close if he gets that speed! But do you really think that bow can push an 440 grn arrow 275? I was guessing more like 255-260.
You're probably closer Dan considering he has a speed loss of around 15 fps(10fps per inch from 30") for DL and about 40 fps for arrow weight(1fps per every 3 gr over IBO weight which for him would be 325gr at 65#'s). With the Drenalin IBO'd at 320 you''re looking at 275 without the string attachments. Add to that the inflated IBO's of today and chances are real numbers would be in the 260 range.
 

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sounds close if he gets that speed! But do you really think that bow can push an 440 grn arrow 275? I was guessing more like 255-260.

My "guessing" is done with On Target 2...and archery software program that calculates these things once given known facts (Bow Model, make, arrow make and model, fletch, DL, DW etc)
 

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OT2 is a great program but it still utilizes mfg stated IBO's if I'm not mistaken. Isn't that correct Kelly?
 
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