Did you know a heavier arrow drops LESS than a lighter arrow??

Mystro · 08-03-2004, 08:12 AM

Yes its true.
Its possible that your heavier arrow will shoot FLATTER out at 30 yards than a lighter one going abit more speed. It has to do with the coefficiency of your arrow weight/speed.
Supper light arrows going blistering fast will not hold the kenetic energy long because they tend to slow down faster than a heavier arrow going abit slower. They dump their energy quicker than a heavier arrow. Food for thought.

Rack-attack · 08-03-2004, 08:18 AM

Quote:

Its possible that your heavier arrow will shoot FLATTER out at 30 yards

I disagree with that...........At 30 yds the lighter is STILL going faster and hitting the target first.

When shot out of the same bow - the lighter arrow will allways hit the target first at all reasonable hunting distances.

They both drop at the same rate of speed - all arrows drop at the same rate of speed - the first to hit just has less time to drop. It takes a long distance for the heavier arrow to catch up and make up for all the lost time.............

Bigpapascout · 08-03-2004, 08:21 AM

HA that is the biggest load of crap I have ever heard!

I use light arrows traveling over 350 feet per second and from 20 to 40 yards I am using only one pin.

can you do that with your heavy arrows?

I didnt think so![8D]

Arthur P · 08-03-2004, 08:22 AM

Well, at 30 yards, I'd have to agree with Rack. Beyond that though... Yes, I've known that since 1989 when I had my bow set up with an overdraw. I was shooting 2216's and decided to try 2213's. Everybody was shooting 2213's for 3D (speed, don'tcha know), and I thought I needed to do the same in order to stay competitive.

When I got the bow tuned and sighted in for the 2213's, my pin gaps were much wider than they were with the heavier arrow. The distance between my 20 pin and 60 pin had gone from 7/8" to 1 1/8".

Fortunately, it only took a week to destroy that dozen 2213's and I was back to the 2216's. But that's what got me very interested in the subject of downrange retained energy with various arrow weights.

By the way, I'm only talking a 60 grain difference between those two arrows. Two arrows with a much wider difference in weight will have widely different trajectories. The light arrow will have a much flatter trajectory. The heavy arrow will hit much harder, even though you might have time to sit and drink a cup of coffee while watching it go downrange.

walks with a gimp · 08-03-2004, 12:21 PM

A 450 grain arrow traveling the same speed as a 350 grain arrow will drop less at longer ranges due to momentum. The key is the same speed, hence I offer the Bowtech BlackKnight as the cure to too much drop

Wiccrman13 · 08-03-2004, 03:20 PM

I don't know about arrows,But Gravity is clear,if you drop a boulder off a cliff at the same time you drop a tiny pebble,they both hit the bottom at the same time,now on the other hand,if you drop the boulder and a feather the feather will catch the air and fall at a slower rate,

So I would be more prone to believe that a lighter weight arrow with feathers would drop slower than a heaver arrow with veins or maybe even a heavier one with feathers,

I would just be more prone to believe that the light weight with feathers would catch more air,and veins would have more presser pushing them down.

08-03-2004, 03:43 PM

Yep, a heavier arrow does drop less, IF, shot at the same speed. Hense your problem, and reason, alot of people go light.

H80Hunter · 08-03-2004, 03:50 PM

Actually I believe physics 101 tells us that every arrows falls at a speed of 9.8 meters/second

so if they are going the same speed, they drop the exact same amount i believe

i could be wrong but i dont know????

08-03-2004, 04:08 PM

Now I think, about it, I beleive your right H80. Only reason my 200gr bullet might not drop as much as my 150 is BC. And I think BC for a arrow, does not apply since you might be using same broadhead.

Arthur P · 08-03-2004, 05:24 PM

Gravity? That's only part of the story. We ain't shootin' in no stinkin' vacuum! You've got to factor in wind resistance!

Wind resistance increases at a faster rate with speed than KE does (velocity^3 for wind resistance of a subsonic object vs velocity^2 for KE). It takes more energy for an arrow traveling 300 fps to fight it's way through the atmosphere and make it to a 60 yard target than it takes for the same arrow traveling only 250 fps.

Use a lighter weight arrow to get it up to 300 fps and you start out with less energy from the bow. Since it starts out with less energy to begin with and uses up it's more of it's already depleted energy simply cutting thru the air on the way to the target, it's pretty easy to see how it's trajectory can deteriorate downrange at a faster rate than the heavier arrow.

Like the shockwave from this airplane, an arrow produces a shockwave. The faster the arrow is going, the more vertical the wave and the more resistance. The slower it's going, the more angled the wave and the less resistance.

I've just got a basic grasp at how this works and don't fully understand the whole thing. So, I wonder if any physicists with specialties in thermodynamics, fluid dynamics and aeronautics would care to take a stab at explaining it to us science dropouts?