I really don't understand how anyone can say that heavier arrows will always increase momentum and KE. When one keeps increasing the arrow weight, the closer that velocity approaches 0. There has to be a breaking point to where arrow weight will start to harm penetration. Momentum and KE just can't increase into infinity.
True. As you increase mass, the momentum increase will be linear. It won't follow a nice bell curve, like someone earlier wanted to see. When you get really close to the extreme end of the bow's efficiency range, the graph will begin leveling out. When you increase mass to the point it exceeds the bow's efficiency range, then KE and momentum will begin falling off, rapidly.
Mean V's post about how his KE drops off with heavier arrows is a perfect example. He apparently hasn't exactly zeroed in on his bow's heaviest efficient arrow, but he know's he's gone over it.
WHAT IS THE MOST EFFICIENT ARROW WEIGHT FOR MY SET UP?
Grab your bow, a handful of arrows of various weights, chronograph and calculator and find out. That's the only way to know for sure. All anybody here can do is make an educated guess. (And some here need quite a bit more education before presuming they're qualified to be making guesses!
)
But be aware that the mechanically 'most efficient' arrow might not be the 'best' arrow for you to use. It might be too heavy to give you an acceptable trajectory. I'm not talking flattest trajectory of course, just acceptable. What's acceptable? That's YOUR call.
Some of these nimrods grew up on the 3D course instead of hunting in the woods. Just like on the 3D range, they bank on arrow speed and flat trajectory to bail their sorry butts out when they screw up - probably when taking a shot at significantly longer distance than they should. These folks can't stand the idea that someone else might have the personal discipline to keep their shots within a defined CLOSE distance (rather than surrendering to the urge to be 'successful' and taking poke-n-hope long range shots), and are thus able to make good use of heavier, slower, more efficient arrows. It's a fact that the closer the distance, the less trajectory is an issue.
This isn't an exact quote, but the meaning is still there: "Archery is the art of seeing how far you can get from a target and still hit it. Bow hunting is the art of getting close enough that you can't miss." Keep that little saying in mind and hunting arrow trajectory should never be an issue.
Just my opinion, of course. Calling it like I see it. Any or all of you have my permission to disagree. I know Sylvan will disagree, given my permission or not. I'm all busted up over it too. [8D]