Shooting Light Arrows

[Kegan]

I think that's all it really comes down to, efficiency. Steve Gardner and others have mentioned that the heavier the arrow, the more efficient the bow will shoot. Hill used a 1700 gr arrow out of a 115# straight bow, and got 31" of penetration. Fred Bear, however, used an arrow around 800 gr if I'm not mistaken though.

Here's how I see it in terms of final killing power. Say you have two bows: one is quite efficient and will shoot a 450 gr arrow at, let's say, 185 fps with no more shock or noise than a 600 gr arrow. The second bow, however, will only shoot the 145 gr arrow 5 fps more than the 600 gr arrow at, let's say 160 fps. However, becase bow two is less efficient, the lighter arrow will also come with more noise and handshock, the energy going into the bow and string and not the arrow.

I shoot these small-diameter 600 gr arrows out of bows 75# or more at times (my heaviest bow, a real dog, being 86#), and am just now starting to think about making a lighter bow of 65#. Given those weights, that 600 gr arrow could be considered "light", with a 450 gr arrow almost a dry fire !

[Steve Cover]

I think that's all it really comes down to, efficiency. Steve Gardner and others have mentioned that the heavier the arrow, the more efficient the bow will shoot. Hill used a 1700 gr arrow out of a 115# straight bow, and got 31" of penetration. Fred Bear, however, used an arrow around 800 gr if I'm not mistaken though.

Here's how I see it in terms of final killing power. Say you have two bows: one is quite efficient and will shoot a 450 gr arrow at, let's say, 185 fps with no more shock or noise than a 600 gr arrow. The second bow, however, will only shoot the 145 gr arrow 5 fps more than the 600 gr arrow at, let's say 160 fps. However, because bow two is less efficient, the lighter arrow will also come with more noise and handshock, the energy going into the bow and string and not the arrow.

I shoot these small-diameter 600 gr arrows out of bows 75# or more at times (my heaviest bow, a real dog, being 86#), and am just now starting to think about making a lighter bow of 65#. Given those weights, that 600 gr arrow could be considered "light", with a 450 gr arrow almost a dry fire !

Explanation finally making sense to me.....  I can now see the reasoning behind the heavier arrow choice. 

Also, it is true that two arrows with the same drag coefficient fired at the same velocity would have pretty much the same trajectory (Within a reasonable velocity range, such as from hunting weight bows). 

So, a heavy arrow would not be giving up much if anything at normal archery shooting distances, and its inherent dampening ability would make it a better choice in a heavy bow..

Thanks for being patient with my ignorance.

Steve

[Kegan]

As far as I can tell, they would have the same tradjectory. Drag really is the only thing that would slow them down.

"Light" arrows make longer range shooting much easier, but at close range (under 30 yards) there wouldn't be much of a change.

Hardly, happy to help

[ryanfromcanada]

Well you can take a log and hit something at 3 miles an hour, and then take a feather and bring it up to light speed and get the same result.  That is plain physics.  What is practical in the real world is another matter.  This is purely conjecture, but I suspect that even the "fastest" compounds can't bring some of the super light arrows up to a high enough speed to get the same effect as the "slower" traditional bows with heavy arrows.  The light arrows will fly flatter and get there quicker, but just won't have as much energy left on target.  I have no idea where the line is and it would take a very scientific approach with release machines and the like to get real results.  .


Swamp

I think that this is ilusstrated well when you look at steel shot vs lead. Nobody argues that the steels better.

[riarcher]

If a 450g arrow is good out of a 45# bow (10g/#),,,
I don't see why you'd need a 1,000g arrow out of a 100# bow?
That same 450g seems just better from the 100# bow but at much less than 10g / #.
To me, that makes the 10gpp rule...... non-applicable?

Anyways, I'm on a venture with Boo & cane arrows. They are light and wonder what I'm going to do for hunting (weight) arrows.

Definately a strong cut on contact BH.
But in a 50# bow where should my weight be and how? Can only add so much weight to the pile end.
Thinik I'll start a new topic on that. Don't want to go off topic too much.

[Mechslasher]

i don't know about steel shot being better.  i've had steel shot bounce off geese and ricochet into the water, 00 buckshot never has  

[Mechslasher]

to me, the 10gpp rule only applies to realistic hunting weight bows for whitetails, 45-65#.  when you get up to 70-100# bows then you can start dropping down to 7-9gpp and still get excellent performance.  500gr arrows are, imo, the minimum wieght to achieve adequate momentum on whitetail size animals.  lighter arrows simply "bleed" off more energy during penetration than heavier arrows.  my favorite set of cane arrows weigh in at 750gr. and one of them was stopped cold on the "matriarchs" neck vertebrae at under 10 yards while the other penetrated most of the length of her body.  i think she would still be walking around today had i been shooting light arrows.

riacher, i'd put a 160-190gr grizzly on the end of your arrows and start hunting.  your foc would go up which would add to your arrows momentum and penetration.  no more worries.

[Kegan]

Riarcher- It goes back to what I say about the arrows also not being heavy enough to use any of the extra energy from the bow due to low efficiency. If you shot a 450 gr arrow from a 100# bow, the bow would bascially try to rip your arm off while the arrow might only go slightly faster than, say, a 65# bow.  That being said, a 500 gr arrow from a bow heavier than 50# but with higher efficiency might be just as lethal as a similiar weight bow shooting a 600 gr arrow, especially if you take into account other factors like fletchings, shaft diameter, recovery speed, and broadheads. It's all a balance, and not a precise science.