ORIGINAL: Paul L Mohr
I think we understand what you were looking for, and I think you probably got the answer you were looking for. However sometimes we post additional information or keep a thread running because there are other people that will read it with a similar question and can get more out of it.
And this was your quote so I was just trying to point out that it wasn't the same, at least as far as archery and penetration are concerned. Some would read that and think it was all the same, light arrow or heavy arrow. As long as it had the same Ke it would act and perform the same way.
I would like to add to my above post as well. For one I mentioned transferring energy. Honestly that means little in archery, you actually don't want to transfer any energy. You want the penetration so you want the arrow to retain the energy, not transfer it to the target. You want energy transfer with a bullet so it causes a larger wound channel.
Also a bow is basically just like a spring or an accumulator. All it does is store energy and release it. How much Ke a bow or arrow has is just an expression of how much energy it can store. If you don't change anything with the mechanics of a bow, like change the draw length or draw weight it pretty much stays at that Ke. Whether you shoot a light or heavy arrow it will still produce nearly the same Ke. It may vary a little bit, but it will normally be pretty close. The only thing that changes is speed and momentum. And the heavier arrow will penetrate better and/or hit the target harder.
The key is to find the point of diminishing returns. A heavier arrow will almost always produce more momentum. What you need to do is find out where it starts to level off with your set up. The difference between a 500 grn arrow and an 800 grn arrow might not be big enough to lose the extra speed and trajectory. But the difference between a 300 grn arrow and a 500 grn may be significant and well worth the lost speed. It's something you need to figure out for yourself though. And the OnTarget software and others are pretty good for charting this kind of information.
I have found with my set up around 400-450 grns is a good medium for me. Someone else's set up may be different.
Paul
As others have said, EXCELLENT post.
ORIGINAL: sngehl01
Clearly, your thinking process is the exact same as mine.
That's what I was thinking the whole time. 60 ft/lbs is 60 ft/lbs. It's like asking what weighs more, a pound of gold ora pound of feathers.
This is exactly the thinking you need, however. A pound of GOLD does weigh the same as a pound of feathers, but if you get to choose which one is going to be thrown at your head at 50mph, which will you choose and why??? Also, as was said before, having that LOW FOC,would make BH tuning a nightmare I believe. Sure, under the "perfect" condition you COULD kill with a 55gr BH, but what's the point??? As Paul finds, I also seem best between 400 and 450 grains, and my hunting set-up is currently about 420gr w/ an FOC around 12%.