I got into a discussion with a 'heavy arrow' shooter & during the conversation he brought up downrange KE vs KE at the bow. His claim is that heavier arrows will have better penetration - say at 35 yards - primarily because of the increased weight.

We've seen the scores of threads WRT penetration & KE but I've never heard anyone make mention of poorer performance down range becasue of the lighter arrows lose energy faster.

I don't know if it makes a difference or not - but it stands to reason to me that it could - if I relate it to steel VS lead shot in waterfowling. The steel comes out of the gate faster but slows faster & delivers less punch downrange.

Does a heavier arrow perform better at longer ranges?

If I shoot a 375 gr carbon & get 61ft/lb of KE is that going to perform worse than a 440 gr arrow with the same KE (as calculated by bowjackson)? (the other tradeoff of course is speed - 270fps to 250fps, yardage estimation & things become more critical)

Thoughts?



Aim small miss small

there's a serious discussion thats been going on for a couple of days on this same bb.....below is the link to the thread.

http://forum.hunting.net/bbs/topic.a...61&FORUM_ID=19

Heavier arrows have more momentum, thus they have better down range energy. Check out the thread on the Bow Hunting forum that is two pages long. Or use the search funtion on this site and type in momentum, I am sure it has been discussed here in detail.

Here is an example with the specs from my bow using the Archery Programs ballistics calculator. With a 26 inch draw and 55lbs of draw weight.

A 312 grn arrow, That is 5.6 grns/lb, I think that constitute a light arrow. This arrow would devolope 41 ft/lbs of energy at 244 fps right off the bow. At 20 yards it would be 35 ft/lbs of energy at 227 fps, and at 40 yards it drops to 31 ft/lbs at 211 fps. Those are not real great figures and typical of what a small guy or a woman would get for performance. All I can say is you better shoot em' close with a wicked broad head, no mechanicals on that set up!

Now we will figure the same bow with a heavier arrow. Lets go with a my aluminums that way 456 grns. This arrow with the same bow would have 44 ft/lbs of energy at 209 fps right out of the bow. At 20 yards it would be 39.5 ft/lbs at 197 fps, and at 40 yards it would be 35 ft/lbs at 187 fps. You give up some speed, but you can see the heavier arrows diffenitely carry more energy than the lighter ones.


Just to see what you would be losing by using the heavier arrow, I will compare the amount of drop from one to other. If you sighted the bow in at 20 yards it would be 2 inches high at 10 yards, and drop 4.5 inches at 25. Then at 30 it would be 11 iches low. Deffinately not one pin accuracy there, but I limit my shots to 25 yards(they are usally closer than 20) and use multiple pins.

Now the 312 arrow would be 1 inch high at 10 yards, 3 inches low at 25, and almost 8 inches low at 30. Not much better than the heavier arrow, you sure don't gain much in reducing judgement errors. You would still need multiple pins.


Those are actual specs from the actual bow I shoot with those exact arrows fired thru a chronograph. Not a calculator guessing what my bow would do off the IBO specs provided by the manufacturer. The only thing I used the calculator for doing the math for me.

Take it for what it is, and make up your own mind. Also note that a much faster bow with a longer draw and more draw weight my have a closer outcome between the two, but it will still fall along those lines. If you had a bow that shot real fast and could shoot with one pin out to 30 yards, a heavier arrow would still give you more momentum, but might slow the bow down to the point where you would have to use multiple pins or guess at shot placement(hold over). And if you were already getting sufficient Ke, what would be the point? That is the argument you will get from the guys shooting lighter arrows. And in that situation, it is a hard one to fight.

Did that help you out any?

Paul

ahhhhh paul why do you think i posted the link to the thread in the bowhunting forum????????

<font size=6>so we don't have to go through 3 more pages of the same posts...LOL<img src=icon_smile_wink.gif border=0 align=middle></font id=size6>

Yeh, I know, I was going to do the same thing as you can tell by my first two lines, then I got carried away, you know me. You posted while I was typing (that took about half an hour by the way!).

Paul

LOL.....yeah been there done that....
ive posted before and it took so long for me to finish that when i posted 2 other peeps posted pretty much the same info <img src=icon_smile_tongue.gif border=0 align=middle>

if you are generating about 61 ftlbs of energy at the bow then it would be safe to say you might be around 45-50 lbs of KE at 60 yards. a lot variables go into figuring this. The length of fletch, fletch height, shaft diameter, etc.

As far as saying the the heavier arrow has more KE, well it depends. both speed and weight have an affect on KE. a light arrow can have just as much KE as a heavier slower arrow. It is safe to say that the heavier shaft will loose less of it's KE at longer ranges than the lighter shaft. How much of an advantage is this? Really it depends, if we are only talking a few ft. lbs of KE at 40 yards if so I wouldn't worry about it.

your question was &quot;If I shoot a 375 gr carbon & get 61ft/lb of KE is that going to perform worse than a 440 gr arrow with the same KE &quot; - It is safe to say the heavier arrow with the same KE at the bow would have more KE at longer ranges BUT this may be only a few ft. lbs. of KE when you actually figure it out. would I trade the speed for a couple more ft. lbs of KE? no way, unless it was for moose.

good luck. you might also want to check out a pc. of software called the archery program. you can graph any sppeed & Ke stuff you want to for your arrow & bow. It is really cool & you could see what you would gain & loose with each arrow choice you mentioned.

ahh.... Go figure - I post a ? & the answer is already out there!

Just goes to show you that you can learn more here by accident than elsewhere by design!



Aim small miss small