carbons and recurves???
01-18-2005, 11:55 PM
#11
Boone & Crockett
Join Date: Feb 2003
Location: Mississippi USA
Posts: 15,296
RE: carbons and recurves???
Think you misunderstood Art--99.99% sure his concern was about the arrow speed being the reason you preferred it. That's why he pointed out that most folks that use carbon on trad bows weight them in some way. Slows them down, but sure helps with penetration.
I figure he's forgot more about archery than I'll ever learn. It's easy to misunderstand on these screens--sometimes you have to read a post a few times to get the meaning that was intended.
Chad
I figure he's forgot more about archery than I'll ever learn. It's easy to misunderstand on these screens--sometimes you have to read a post a few times to get the meaning that was intended.
Chad
01-19-2005, 07:04 AM
#13
Giant Nontypical
Join Date: Feb 2003
Posts: 9,175
RE: carbons and recurves???
Actually, I understood the question perfectly. Just did a terrible job of making the point I was trying to make.[&o]
There are two things needed for establishing a bowhunter's effective range. Being able to hit where you're aiming is only half the story. Hitting with an arrow that has enough power to give enough penetration for that quick, clean kill is the other half.
Silverbackpete, here's the deal. For a long time, I was confused by all the talk I was hearing from the compound guys, about how well their light little knitting needle arrows were penetrating in game. It didn't make sense. We all KNEW you had to have at least 9 grains of arrow weight per pound of draw weight for decent penetration on game. Was it the speed? Did it have something to do with the kinetic energy numbers they were coming up with, 70, 80... even 90 foot pounds?[:-] Kept me stymied for a long time, until I got on the ballistics table calculator at www.bowjackson.com and did some numbers crunching.
Well, I decided to run the numbers on an "IBO" arrow, 350 grains at 300 fps, and compare it to a more traditional arrow, twice as heavy and half as fast - 700 grains at 150 fps - like you might see from a selfbow. So... the 700 grainer came out with 35 foot pounds and ..4655 pound/seconds of momentum. The 350 grain arrow came up at 70 foot pounds and .4655 pound/seconds of momentum.
THERE was my answer! It wasn't the speed or the KE, the light arrows were traveling fast enough in those hard cam bows to equal a heavy arrow's MOMENTUM! They had to travel at twice the speed and with twice the energy of the heavy arrow to do it, but they did it.
Well, when you go without those hard cams and shoot a recurve, they don't look so good.
Slow that 350 grain arrow down to 200 fps, which is realistic for a 50 pound recurve, and you get 31 foot pounds and .3104 pound/seconds of momentum. The lighter arrow doesn't cut through the air very well, so it slows down as it goes downrange. At 30 yards, wind resistance has cut it's speed to 183 fps, KE drops to 26 ft lbs and momentum has slid to .2838 pound/seconds.
Take a 500 grain arrow with the same bow. It'll likely shoot around 180 fps for 36 ft lbs and .39904 pound/seconds of momentum. The heavy arrow still loses some to wind resistance, but it does much better than the light one. At 30 yards, it arrives going 170 fps with 32 foot pounds of energy and .3760 pound/seconds of momentum.
The light arrow flies flatter to make it easier to hit at longer distances, but carries a lot less 'oomph' downrange for penetration potential. The heavy arrow has a higher trajectory, making it problematic to hit at longer distances, but it carries a lot more of it's power to where it's going.
You need to balance the flat trajectory with enough power to do the job. It doesn't do any good to be able to hit a deer at 35 yards if the arrow only makes a flesh wound and bounces off. Or, even worse, gets only one lung and leaves you with a long, fruitless tracking job.
That's what I meant by being concerned about your reasoning for using carbon arrows so you can make good hits downrange. It doesn't do any good to be able to hit 'em if your arrow doesn't carry enough power with it to finish the job.
There are two things needed for establishing a bowhunter's effective range. Being able to hit where you're aiming is only half the story. Hitting with an arrow that has enough power to give enough penetration for that quick, clean kill is the other half.
Silverbackpete, here's the deal. For a long time, I was confused by all the talk I was hearing from the compound guys, about how well their light little knitting needle arrows were penetrating in game. It didn't make sense. We all KNEW you had to have at least 9 grains of arrow weight per pound of draw weight for decent penetration on game. Was it the speed? Did it have something to do with the kinetic energy numbers they were coming up with, 70, 80... even 90 foot pounds?[:-] Kept me stymied for a long time, until I got on the ballistics table calculator at www.bowjackson.com and did some numbers crunching.
Well, I decided to run the numbers on an "IBO" arrow, 350 grains at 300 fps, and compare it to a more traditional arrow, twice as heavy and half as fast - 700 grains at 150 fps - like you might see from a selfbow. So... the 700 grainer came out with 35 foot pounds and ..4655 pound/seconds of momentum. The 350 grain arrow came up at 70 foot pounds and .4655 pound/seconds of momentum.
THERE was my answer! It wasn't the speed or the KE, the light arrows were traveling fast enough in those hard cam bows to equal a heavy arrow's MOMENTUM! They had to travel at twice the speed and with twice the energy of the heavy arrow to do it, but they did it.
Well, when you go without those hard cams and shoot a recurve, they don't look so good.
Slow that 350 grain arrow down to 200 fps, which is realistic for a 50 pound recurve, and you get 31 foot pounds and .3104 pound/seconds of momentum. The lighter arrow doesn't cut through the air very well, so it slows down as it goes downrange. At 30 yards, wind resistance has cut it's speed to 183 fps, KE drops to 26 ft lbs and momentum has slid to .2838 pound/seconds.
Take a 500 grain arrow with the same bow. It'll likely shoot around 180 fps for 36 ft lbs and .39904 pound/seconds of momentum. The heavy arrow still loses some to wind resistance, but it does much better than the light one. At 30 yards, it arrives going 170 fps with 32 foot pounds of energy and .3760 pound/seconds of momentum.
The light arrow flies flatter to make it easier to hit at longer distances, but carries a lot less 'oomph' downrange for penetration potential. The heavy arrow has a higher trajectory, making it problematic to hit at longer distances, but it carries a lot more of it's power to where it's going.
You need to balance the flat trajectory with enough power to do the job. It doesn't do any good to be able to hit a deer at 35 yards if the arrow only makes a flesh wound and bounces off. Or, even worse, gets only one lung and leaves you with a long, fruitless tracking job.
That's what I meant by being concerned about your reasoning for using carbon arrows so you can make good hits downrange. It doesn't do any good to be able to hit 'em if your arrow doesn't carry enough power with it to finish the job.
01-19-2005, 07:46 AM
#14
Join Date: Feb 2003
Location: Miami FL USA
Posts: 208
RE: carbons and recurves???
I agree with Arthur P about the value of arrow weight in penetration. AP and others are have hashed this penetration issue out time and time gain on another forem.
There are other issues besides arrow speed and weight that also come into play and effect penetration. Like arrow drag through the animal. Factors like the broadhead and shaft design that you are shooting. I've found that I gotten better penetration from a two blade cut to the tip over say a snuffer design. The snuffer has greater drag, and in my case should be shot at thinner skinned animals like whitetails, not hogs unless I'm shooting a heavier poundage bow. If you shoot a tapered carbon shafts like the Arrow Dynamics Traditionals the head opens up channel where the decreasing sized shaft slides through with less resistance.
There are other issues besides arrow speed and weight that also come into play and effect penetration. Like arrow drag through the animal. Factors like the broadhead and shaft design that you are shooting. I've found that I gotten better penetration from a two blade cut to the tip over say a snuffer design. The snuffer has greater drag, and in my case should be shot at thinner skinned animals like whitetails, not hogs unless I'm shooting a heavier poundage bow. If you shoot a tapered carbon shafts like the Arrow Dynamics Traditionals the head opens up channel where the decreasing sized shaft slides through with less resistance.
01-19-2005, 11:23 AM
#15
Join Date: Mar 2004
Location:
Posts: 881
RE: carbons and recurves???
Silver I think the point that is being made is this. Speed don't matter on a recurve, sorry but it don't. I understand that making wood arrows is not everyone's cup of tea. However, if you have to make the carbon arrows heavy, why not shot alluminum? Shooting carbon arrows does not make for a quick clean kill. Carbons would be the worst for this, speed doesn't matter, its penetration. If I get a pass through I get a pass through. Speed of your arrow doesn't make a deer die faster.
Why do you want to shoot carbons over alluminums?
As for the comment on wood and breathing animals.[:@][:@][:@][:@][:@][:@][:@][:@]
I don't know what made that opinion.[&:]
Why do you want to shoot carbons over alluminums?
As for the comment on wood and breathing animals.[:@][:@][:@][:@][:@][:@][:@][:@]
I don't know what made that opinion.[&:]
01-19-2005, 11:38 AM
#16
Boone & Crockett
Join Date: Feb 2003
Location: Mississippi USA
Posts: 15,296
RE: carbons and recurves???
Hey Art--my fault that time. I didn't mean that you misunderstood, I was saying to Pete that I believe he misunderstood you. Dang computers.....
Nope, arrow weight isn't the only thing that affects penetration, but it is a big factor.
Ewolf, speed does play a part, but you don't want to give up momentum for speed. A 700 grain arrow travelling at 180 fps will out-penetrate one traveling at 150 fps, all else being equal. There is always that point of diminishing return too--you don't want to shoot an arrow that is so heavy that it drops to the ground at 10 feet (think that would be considered a spear anyway [8D]). I've never done any experimenting with that, but from what I've read it seems to be around 12-13 grains per lb of draw weight on average. That's when it gets to the point that the increased arrow weight will not make up for the speed lost.
It's the kind of stuff that makes my brain itch. I'm not going to get down to the bare minimum, so I'm not going to worry about doing the math just yet. My guess is I could kill a buffalo with a 70# bow, so I'm going with an 85# just in case.
Chad
(edited because I can't spell)
Nope, arrow weight isn't the only thing that affects penetration, but it is a big factor.
Ewolf, speed does play a part, but you don't want to give up momentum for speed. A 700 grain arrow travelling at 180 fps will out-penetrate one traveling at 150 fps, all else being equal. There is always that point of diminishing return too--you don't want to shoot an arrow that is so heavy that it drops to the ground at 10 feet (think that would be considered a spear anyway [8D]). I've never done any experimenting with that, but from what I've read it seems to be around 12-13 grains per lb of draw weight on average. That's when it gets to the point that the increased arrow weight will not make up for the speed lost.
It's the kind of stuff that makes my brain itch. I'm not going to get down to the bare minimum, so I'm not going to worry about doing the math just yet. My guess is I could kill a buffalo with a 70# bow, so I'm going with an 85# just in case.
Chad
(edited because I can't spell)
01-19-2005, 11:45 AM
#17
Join Date: Mar 2004
Location:
Posts: 881
RE: carbons and recurves???
Ewolf, speed does play a part, but you don't want to give up momentum for speed. A 700 grain arrow travelling at 180 fps will out-penetrate one traveling at 150 fps, all else being equal.
01-19-2005, 01:25 PM
#18
Thread Starter
Join Date: Nov 2004
Location:
Posts: 74
RE: carbons and recurves???
So much input WOW!! thanks all of you,,, I am going to leave the carbons with my compound,,,,,, in the back of the closet , I going to shoot the wood w/ the 2 blade Zwickeys and have a hell of a time. Pete
