mobow

Absolutely. These are just laws of physics, not anything I'm pulling out of thin air. A heavy arrow will not slow down as fast, thus retaining it's KE longer than a light arrow? Why? Because it had more to start with, and, it's not slowing down as fast.

The formula for KE is speed x speed x weight / 450240. If KE is directly related to weight and speed, and the heavy arrow has more KE to start with, AND retains it's speed longer......You do the math, no way the light arrow can keep up. Laws of physics....It CAN'T....

Go back to the rock. It's the same principle.....Which one goes farther? The heavy one, I guarantee it.

Go back to my arrows......355 grain arrow, flying 318 = 79 pounds of KE.

490 grain arrow, flying 282 = 86 pounds of KE, AND it won't slow down as quickly. Which one has more downrange energy?

twildasin

Im not trying to be difficult here by no means...just learn. I understand your physics and all but it does not sound correct. Ok back to your rocks if one weighs 20 pounds and one weighs 5 pounds and you shooot them the one weighing 20 pounds is traveling 100fps. the one that is 5 pounds ia traveling 300fps i dont see the bigger rock going farther nor do I see it maintaining its speed as long thus dropping quickly to the ground!
Ohwell if im shooting an animal at 50 yards I would want light and fast-vs- slow and heavy. Thats just me Ive never had a problem with my arrows sticking in the dirt and if they are in the dirt you got plenty of penetration!

KodiakArcher

Yep, It's a proven law of physics, as expressed in Newton's First and Second Laws of Motion.

GMMAT

I sorta see the light, fast arrow as a dog chasing cars.

What's he gonna do when he catches it?

Paul L Mohr

A heavier arrow will always penetrate better than a light one when shot out of the same bow because it carries more momentum. KE is only part of the figure and not the most important part in my opinion.

That being said using a light arrow really depends on your set up. Most people shoot enough energy with modern compounds that it really isn't an issue on deer at normal ranges. Now when you are talking lighter set ups like mine with a short draw length and lower draw weight it starts to make a difference. For someone like me it pays to play around and find a good midway point. If I go too light I won't get pass throughs, if I go too heavy I start to really lose speed, I'm talking under 200 fps.

However for someone shooting a newer bow with more than 60 lbs and 28 inches or more of draw length you could darn near shoot any weight arrow you wanted if you used a sharp head and picked your shots well.

My opinion anyway.

Paul

MeanV2

Ok, I'm not really pro light arrows or pro heavy arrows. I use both depending on the game I am after and the expected shot distance. These numbers were out of the same bow (60# 28" Guardian) arrows weighed on the same grain scale, and shot through the same Chrono. You might find them interesting

326 grain CX Maxima 280 fps 56.77#KE

497 grain FMJ 232 fps 59.41#KE

171 grain heavier arrow lost 48 fps and only gained 2.64#KE

Dan

GMMAT

As a novice (in anyting techie) I'll ask a pertinent question, then, Dan.

At 25yds.....how much difference in arrow drop between the two. Let's put this into perspective.

KodiakArcher

But remember that KE is not the only factor that needs to be looked at and is generally considered to be irrelevant when discussing penetration (or impact) between two bodies. Momentum must also be considered and if you look at the formula (mass x velocity) you'll see how the heavier arrow has the advantage here; 91280 grain-feet/sec. vs. 115304 gain-feet/sec. in your examples.

mobow

LOL.....well......the 5 and 20 pound rock really isn't a good example, because the average person isn't capable of throwing a 20 pound rock very far.....but I promise it will hurt more if you get hit by it....

Look back at my numbers. The heavy arrow has more KE right at the start.....it's a law of physics that it won't slow down as fast, so how is the light arrow going to have more down range energy?? Stop for a second, and think about it. Where is the light arrow going to catch up at? If it's slowing down faster, and had more KE to begin with....where will the light arrow make up for it?? It simply can't.

Let's say the heavy arrow, flying 282, is flying 272 at 30 yards. Now, the light arrow slows down faster, again...law of physics, cannot be refuted....it's a proven FACT. So, the light arrow is that was flying 318 is now flying 303 fps.....do the math.

490 grain arrow, at 30 yards, = 80.5

350 grain arrow, at 30 yards, = 71.3

See?? Those are fictitious speeds, but they are close. I slowed the heavy arrow down 10 fps, thelight arrow 15.

I'm sure someone w/ on target software can give exact speeds here, but those are close. There is simply no way the light arrow can make it up...

Kanga

Lets look at this another way.

What is going to travel farther a ping bong ball travelling at 300fps or a golf ball at 250fps and which one is going to hit harder when it arrives. My money is on the golf ball

Another thing about a heavy arrow is it will absorb more of the bows energy thus making the bow a little quiter and have less hand shock.
A light arrow is not going to absorb all the bows energy and that energy has to go somewhere namely back through the limbs into the riser the end result more noise and hand shock.

Go over to the trad gang's web page and read the test results from Dr Ashby about penetration, FOC etc