Thanks Bry, I really don't know much about other animals or their structures other then the one's found here in the States. I guess I don't do much hunting outside of the one's that don't ussually fight back <img src=icon_smile_blackeye.gif border=0 align=middle>. I told my wife one time that if I were not married and have a family that I would love to hunt a grizzly with a bow. But since I do, I don't have a great desire anymore. Family life made me a little more cautious of what I do with my body and potential harm.


Thanks Arthur, so then my setup would be at least legal on Cape Buffalo. Not that I'm going anytime soon!<img src=icon_smile_cool.gif border=0 align=middle>

Edited by - BobCo19-65 on 08/22/2002 14:51:21

Arthur, that's probably a smart choice.

Bob, I know what you mean. I have no desire to hunt cape buffalo, or hippos, or rhinos, or elephant. I do plan on going to the dark continent to hunt some plains game and lion with my bow. However, when I'm after lion I will have a guy with a big gun behind me. I'm brave, but not stupid.<img src=icon_smile_wink.gif border=0 align=middle>

HuntingBry, LOL, I hear ya man, I hear ya!

<BLOCKQUOTE id=quote<font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote>
In South Africa, the regulations call for a minimum 80 ft lbs of KE and 700 grain arrows for Cape Buffalo, and 105 ft lbs of KE and 850 grain arrows for hippo, rhino and elephant.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

Dang! I'm going to have to start working out if I ever want to shoot an elephant. How much draw weight am I going to have to pull (on average) to get an 850 grain arrow to produce a KE of 105?

Straight, I don't know what draw weight you would have to use, but the 850 grain arrow would have to be moving a minimum of 236 fps to get 105 ft-ibs of KE. The draw weight would also depend on your draw length.

After doing the math on the setup that I was considering, I came up with an arrow that weighed 788 grains now add weight tubes or weed eater string and that should put me where I need to be. The question is more like would my shoulder still hold up to shooting 100lbs. I have shot 100lbs or more on several occasions but I have never shot it for an extended period of time so I really don't know how well I would take it.

Protect your hunting rights, &quot;Spay or neuter a liberal.&quot;

Like HuntingBry, I'm totally enjoying this topic and truly LMAO with the &quot;sideshow&quot;!! Here's my anology for you Arthur AND BobCo19-65: Ever see the show where Patrick Swazye is the return to earth ghost,.... and the scene where he's trying to warn his wife of his friend putting moves on her,...but no one can &quot;see&quot; or hear him? Well,.....all I can say is that's what popped into my head!! Follow me??!

Amosgreg:
What I was trying to say was that penetration isn't necessarily liner with KE. This didn't show in Norb's tests...as he really didn't go very light. Even in the Modern Bowhunting article they only went down to 400gn yet the faster/lighter arrows out penetrated the heavier slowers arrows in both mediums...even though the lighter arrows had LESS KE.
KE goes up with velocity, but I think penetration would be more curvlinear than linear. In otherwords, ALL else being the same as you add speed, you will start to see a progressive increase in penetration, not linear.

To go along with the ping pong vs. golf ball thing. You guys are 100% right. Some bows work better at a certain end of the scale than others. But for penetration (read cutting) BOTH will need to go VERY FAST to &quot;cut&quot; anything.


In answer to the original question. &quot;Does KE=penetration?&quot; I say No....but it's close enough for government work.

Edited by - Stealth_Force on 08/23/2002 03:30:52

Ok Stealth I see what you are saying and the formula says the same thing! Since Velocity is one of the factors in figuring out KE (Weitght of the shaft the other) If there is a change to one KE changes.

If you shoot an arrow out of a bow and srart heavy and then progressively get lighter the KE will continue to go up.

If on the other hand as the arrow gets lighter we turn the poundage of the bow lower in order to keep KE the same... the penetration will begin to decrease at distance.
Again it is a relationship.

Africa,
I read an artlcle about a bowhunter who hunted Elephant to prove to the Natural Resources folk in a country that the bow was a ligitament tool for hunting Dangerous Game.
I'll pull the article and quote his set-up but I believe he was shooting an 75-80 pound bow with custom Aluminum shafts that weighed around or over 1000 grains. I forget what broadhead he was using but it was 150 grains or so.

Me, I want to hunt leopard with the bow but Lion (the PH with a big bore is required for all DG!) is a different matter to me!

Cape Buf, Rhino, Hippo, Brown Bear and Grizzly are just too dangerous for me to hunt with a bow. (nope... not enough testosterone for me <img src=icon_smile_big.gif border=0 align=middle>)

I have had to opportunity to go over twice and I will go back! The cost is about the same as a full 1x1 Elk hunt in AZ, MT or NM including travel and license and if you shop around this would INCLUDE trophy fees for up to 7 animals!
My first trip I stalked several Nyala, Blue Wildebeast and Impala. I took an Impala and had an arrow-eating tree <img src=icon_smile_sad.gif border=0 align=middle> on a beutiful Nyala bull.

I have elk hunted Montana and Colorado and had a 5x5 within 15 yards and several other bull within 100 but not the number of game nor the stalking as I had in Africa.






Greg

&quot;Getting close to the game is the joy of Bowhunting for me, the harvest is a bonus.&quot;

Live 15 ft Python after eating a small Antelope!

Greg,

<BLOCKQUOTE id=quote<font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote>If you shoot an arrow out of a bow and srart heavy and then progressively get lighter the KE will continue to go up.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

<font color=green>BUT THAT IS NOT WHAT HAPPENS!</font id=green> It's just the opposite. Dropping arrow weight increases speed but decreases KE due to efficiency. As you go lighter, the arrows gradually lose their ability to absorb stored energy from the bow.

The only way you can gain KE by going lighter is if you start with an arrow that is grossly too heavy for a bow, like a 1000 grain arrow on a 30 pound bow.

Archery is a game of tradeoffs. A bow has only so much energy that it can store and give back to an arrow as speed, KE and momentum. If I were beaten back into a corner and had to say which arrow would penetrate best while giving the best trajectory per penetration potential... I'd be inclined to go to a chronograph, do what Mullaney does and shoot arrows in 50 grain steps from heavy to light, graph the speed and KE, then choose the arrow weight where the two lines intersect. And that weight is going to be somewhere in between the two ends of the weight scale. Between 6-8 grains per pound of draw weight, depending on bow design.

Start at the arrow weight on the graph where the two lines intersect and use that as your baseline arrow weight, speed and KE. Above the weight and below that weight, that's where you get into the tradeoffs. Does lighter/faster for slightly better trajectory but less KE and less momentum do more for you than baseline? Does heavier/slower but with more momentum, more KE and quieter shooting do more for you than baseline?


Twang, I see what you're getting at, just don't know for sure which direction you're going with it.

Edited by - Arthur P on 08/23/2002 07:43:23