Alright I will throw in my opinion. Both KE and Momentum (p) have there place in physics. When attempting to estimate the penetration power, so to speak, of your arrow I think "p" might be a better route. p is basically a way of measuring inertia, since inertia is a principle and can't be measured directly (p is most comprable). Inertia is a principle which states an object will remain at a current state untill acted on by an outside force. It something is sitting still, it will continue to do so until acted on be a force. If something is moving, it will continue to do so until acted on by an outside force. This pertains to a flying arrow. How much inertia (momentum) an arrow has dictates how much force is required to stop it.

P.S. THis is downscaled to be more easily understood. Everthing is reletive; however not 100% correct. Inertia and p are not interchangable, but for practical purposes...


[8D]

That was when I was young and dumb, nodog. I guess the general purpose was to do what every other mother's son - shooting those extremely high draw weights - was doing.... Prove my superior manliness by shooting a bow few others could draw.[&:] Kinda what people are doing now with chronographs and bragging about arrow speed. Same concept.

I find it interesting to look into the actual properties we can measure to determine if that recent big archery purchase was worth it or not[ Also, if short draw and light draw weight shooters can pick up some extra penetration for hunting and or flatter trajectory,, that is a definate plus also. I'm very pleased to find that my 60 pound Allegiance is actually preforming like a 70 pound compound and the only way I could have was to measure everything like I did.

I've reloaded hi power rifle and pistol ammo for about 30 years and find that very interesting also,,, ballistics is fun stuff

I know my 60 pound ProTec shoots the same arrow every bit as fast as my 80 pound ProVantage did. Getting the same performance at much less draw weight is very nice on the shoulders now that I'm getting OLD and gimpy. But you've gotta admit there is a lot more swell-chested bragging about arrow speed these days than on any other aspect of archery or bowhunting.

Probably but more speed is a great thing to have if YOUR accuracy isn't sacrificed I don't go for the extra speed with light arrows, I use the extra speed that it gives my heavy arrows for hunting. My current 484 grain hunting arrows are going 257 fps and quietly. Just looking at the 257 fps won't get much attention but 71 lbs. K.E. from the 60 pound bow is the best benefit for me

I'm getting old too, working on the boy's car today found me getting up off the shop floor MUCH slower than I used to[:@]

For me, getting more speed is okay, but I always ask the question, "What did the manufacturer do to give me more speed?"

If they reduced the brace height, gave me more reflex, or made the draw force curve steeper, then I don't necessarily want it. If the reason was a more efficient design, leaving me with a bow that is as forgiving as I had in the past, then I'll take the speed without complaining in most cases.

However, there does come a point where too much speed will take away from archery (in my opinion). I used to like watching the flight of my arrow. I don't see the arrows so well today. I use to like the challenge of using a weapon where few could get close enough to make a kill. Today, it can be done at distances that approach what I'd take with my shotgun. I use to enjoy the practice that was required to become proficient. Today's beginner is a better shot within 2 weeks of steady shooting then an experienced archer of 30 years ago. The lines are starting to blur and it's becomming less and less of a primitive weapon and more of just an efficient weapon of choice. I know that this doesn't bother most, but for some reason it takes away from what I always felt archery hunting season was meant to be.

Man isn't that the truth! If speed increase doesn't come from efficiency improvement then there is a price to be paid for it. I think a lot of archers only look at peak weight and assume that if 1 70# bow shoots faster than another 70# bow than the faster bow is better and it will be just as easy to shoot.

Arthur, I have tried to just accept that we are not communicating regarding this but I can't help myself. Regarding the fly wheel, again I agree that it has direction but again, I'm trying to focus on an analogy with archery. Let me ask you this, when you shoot an arrow you can say what direction it is going in the context of North, South East or West. A vector! In this context what direction is the fly wheel going? What direction is a tuning fork going? Kinetic energy is defined as the energy a body posseses because of its motion. Any motion! But in archery it is limited only to the motion of the arrow moving toward the target. Kinetic energy as the result of the type of motion exhibited by a fly wheel or a tuning fork are SPECIFICALLY NOT INCLUDED when we ALL talk about the KE of an arrow. Call this re-writing physics if you like but that is how its done in archery. You are arguing "technicalities" from a pure physics perspective that in my opinion only tends to confuse the issue. You seem to think I don't understand what you are saying but I understand what you are saying very well. I simply disagree with you. IMO you are trying to force a general text book definition to a specific case and failing to understand the ramifications of the specific case.

Hey, what do you really think of KE. Personally I use KE for a reference point, something to work off. But my main objective is to hit the !@#$ animal.

And I'm going to keep insisting for you and others to quit bending the definitions. The physics of archery are no different than the physics of everything else. If the definiton of KE does not fit the problem, then you look elsewhere to find the answer. Any confusion is being caused by randomly assigning new definitions to scientific terms to make them fit a preconcieved idea. Stick with the true definitions and confusion would dissolve.

This preoccupation with KE is a thoroughly modern invention - within the past 17 years - brought on by those who want to use the same ultralight arrows for hunting that they do for shooting targets - specifically 3D. And yeah, when you're using ultralight arrows, you need to know the paramaters that you're working under. People have keyed on KE because that's what's easiest to figure, not because it's scientifically applicable. They've keyed on it because they like speed, and they can achieve a healthy amount of KE with speed. They WANT to believe KE is king, so they bend the laws of physics around like playdough to "prove" their point of view.

Mullaney? He makes his living off the archery industry. The industry is making fistfulls of money off the speed cult. They are actively cultivating speed so they can make ever more money. Surely it's no suprize that Mullaney can be paid to write an article expounding the virtues of KE, because speed and KE is what's selling. I don't blame him a bit for greasing the wheels that feed him. Am I being overly cynical? I think not.

Hunting with a very light arrow is very much akin to trying to boat a 15 pound bass on 4 pound test line, using a heavy action flippin' stick. That line is severely mismatched to that rod and the fish. It can be done, but you can make no mistakes.

Substitute arrows less than 400 grains for 4 pound test and 70 pound, high performance compound for flippin' stick and you've got an elk hunter doing exactly the same thing. Using an arrow that is severely mismatched to the bow and to the game. It can be done, but you can make no mistakes.

If you're going after that bass with 30 pound test on your flippin' stick. The line is matched to the rod and to the fish. A mistake or two is not going to cost you the fish. Increase arrow weight to 500 grains on that 70 pound bow, and you've got one deadly combination for that elk hunter. He just has to work a little harder at knowing the exact distance of the shot. Easy enough when you've got a lazer rangefinder in your pocket. Not so?