FOC increase

[Pushbutton2]

FOC increase

Different mechanism of course...

Of course.

I was reminded of a grade school science lesson by your post.

With out the thumb it didn't have the spine, with the thumb it does. p

[muddyfuzzy]

Sounds like you are right where you need to be.

you know thinking about this again you might want to consider taking a turn out of that bow and ditching the 100's for 125's, just an option.

[enewman]

Here is the velocity. I just cannot get them to fly as good as the bloodsport arrows. I'm going to remove some weight and see if I can stiffen them up a little. I will say once I shoot these arrows up I want be buying anymore. This arrow has a 23.95 foc.

Sorry about the mess on the table

[Pushbutton2]

Do you guys know the formulas for figuring out Momentum and KE? I'm thinking of adding the to my spreadsheet

[enewman]

Ke = mass x velocity x velocity / 450240



Momentum =. Mass x velocity / 225418


If you look around there are some slight variations
but this will get you very close

[bowhuntntxn]

Push button I have a question about your spread sheet if I may. I presume the GW column is the gross weight. And you have two arrows that have identical data entered but the FOC is different. How is that possible?

To change that number wouldn't the GW have to be different to make any other variable change? It kinda has me thrown for a loop right now.

[Pushbutton2]

Ke = mass x velocity x velocity / 450240



Momentum =. Mass x velocity / 225418


If you look around there are some slight variations
but this will get you very close

Thank you!!!

[enewman]

Push button I have a question about your spread sheet if I may. I presume the GW column is the gross weight. And you have two arrows that have identical data entered but the FOC is different. How is that possible?

To change that number wouldn't the GW have to be different to make any other variable change? It kinda has me thrown for a loop right now.

I think I saw where the two arrows had different vanes

[Pushbutton2]

I just updated my spreadsheet. I used the formulas enewman posted. Thank you again!!!

I look a it and my mind almost goes into overload. I think I need to simplify it or condense it. Just not sure what to cut or move....

Another thing I noticed was there wasn't a big jump in KE and MO Numbers like I expected. So now I'm kinda wondering if this has been worth it?
I imagine bowhuntntxn is going to say "Told you so :-p" LOL

Let me see if I can post the PDF version of my spreadsheet.

[Pushbutton2]

On a positive note I just learned how to post pictures from my PC to TBH :-)

[enewman]

Ok I don't see how the expedition and the xt have the same weight but different speeds. Only way that can happen is if the xt is not flying straight.

[bowhuntntxn]

No I am not going to say that. But what I will say is that you gave it a lot of effort, and hopefully learned some things along the way. And that in itself made it worth it IMO.

The reason the numbers for KE and momentum don't make huge jumps, is because they are both dependant on velocity, which is dependant on total weight, which is a function of spine. Meaning to have the right stiffness in spine for you, you will have to jump up the total arrow weight a ton, which in turn will kill the speed, thusly affecting both KE and momentum.

[Pushbutton2]

Ok I don't see how the expedition and the xt have the same weight but different speeds. Only way that can happen is if the xt is not flying straight.

that's was the speed when I had 40 grains tip weight in it. I just fixed it. I think. Let me quadriple check. :-)

I added 10 grains to the tip and lost 5 fps
but now that i'm thinking about I my weights wrong on it as well

[bowhuntntxn]

I think I saw where the two arrows had different vanes

Then wouldn't that mean there are two different gross weights? Surely the different vanes with the same weight won't affect FOC will it?

[Pushbutton2]

Then wouldn't that mean there are two different gross weights? Surely the different vanes with the same weight won't affect FOC will it?

I just fixed that. I think.....

I need to get ready for Church. I'll be back on later.
I hope you are going to Church too :-)