No. You aren't backward on that at all. That's 100% correct. But with a heavier nock (weight on the back of the arrow) it does just the opposite; stiffens the spine. It is possible that long of an arrow with a 125 grain point is a tad weak in the spine.......I dont' have On Target software or I would run it for you......I will, however, go check eastons chart.....brb....
The 500 checks out just fine. Not even really borderline. BUT, if you've got an aggressive cam......it could be a tad weak. My money is still on the better nock theory.....
I'm using the nocks that come with the shafts ('cept for the arrows with the Firenocks on 'em). I'll try putting firenock nocks on without the lighted part in them to see if they work better than the factory ones. I'm pretty sure the Equalizer has a pretty aggressive cam. Not sure about that one tho' either. This stuff is making me feel stupid.
Yeah, FOC gets fairly complex sometimes. The very short version is........TOO much attention is paid to it. Arrow spine is more critical than FOC. If you're using glue in inserts with screw in points......It's gonna be pretty difficult to have your FOC to the point where it's just too small. Jeff was able to get below 1% because he was using glue in points. The TOTAL point weight of his arrows were 50 grains. No insert, nothing. Just the point. Spine is where it's at. And good nocks. I've hunted with as low as 9% (with fixed blade BH's) and as high as 15% (with mechanical) and they both flew extremely well. I think sometimes we overthing what we're doing a little bit. Working in a pro shop I see the "average" individual, and being on bowhunting.com I see us guru's as well. Those of us on here have MUCH more info than the "average" archer and sometimes I feel like maybe we overcomplicate the issue. We read that FOC HAS to be above 12% for hunting. There is no question that high FOC has its definite advantages. But it's very easy for us to 'think ourselves dumb' if that makes sense. We overthink the issue and dumb ourselves down some. The bottom line is.....if your arrows are spined right, you're bow is well tuned, your arrows are flying straight and hitting where you want them too.........Well, what more is there really?
Well I just checked It again using the formula BobCo gave me In a link on HNI. Here's that link- http://www.ubbc.ca/resources/documents/archive/understanding_and_applying_foc.pdf Here's the results using 2 different methods- Including the tip- 7.7% Not Including the tip- 12.1% According to Ashby I should go by the 1st result. I've never had a penetration problem but I can say this that this summer I'll be experimenting with this and most likely I'll be adding brass Inserts to get my weight and FOC up. Currently right now my arrows weigh In at 561 grains. That Includes my 125 grain Snuffer. What method are you all using?
I always calculate using the tip, the whole arrow. In my mind, to calculate the FOC without including the tip would not be correct as the tip is part of the arrow. Schultzy, when you start upping your tip weight you may need to use a shaft with a bit stiffer of a spine, depending on what you are using now.
Did you get the numbers mixed up? The reason I ask is that the % should be higher with the tip included than it is without.
My arrows are 33 7/16 long with the Broadhead (33.4375). Without the broadhead they are 31 1/16 (33.0625). My arrow balances at 19 5/16 (19.3125) with the broadhead on. With the broadhead- 19 5/16 / 33 7/16 - .50 * 100= 7.757% Without the broadhead- 19 5/16 / 31 1/16 - .50 * 100= 12.17303% I didn't check the balance point with the broadhead off, I did It with the broadhead on. When I measured the arrow for length I only measured to the end of the arrow and not the end of the broadhead. It really doesn't even make sense to do It this way If your not going to Include the broadhead. That's why I was asking how everyone else figures there FOC out. Bruce, Just for the heck of It I checked the FOC without my broadhead all together. My balance point this time was at 16" without the broadhead. 16 / 31 1/16 - .50 * 100= 1.50905%
You should recheck the balance point with the broadhead off. Also, without the extra length of the BH the center point will change. I never fool with FOC without a tip only because it seems irrelevent to me. I wouldn't shoot the arrow without a tip (at least not on purpose and I only did it once LOL) so I don't take measurements that way.
The balance point did change Bruce. Previously It was 19 5/16 with the broadhead. Without the broadhead the balance point was 16". Oops!! That's funny!!:d
