FOC 2 ways

[nub]

I' m trying to figure FOC for a head I haven' t purchased yet. When I figure it for my existing head(125gr muzzy) useing the ACC arrow weight calc. I come up with 12.4%. When I acually balance with the head on, and measure differences, I come up with 10.7%. Now I' m assumeing the second way would be the most accurate. If I use the arrow weight calc. example to find the difference between a 125 and a 140 gr. (only 1.2 %), can I add that difference to the 10.7% accuall and expect a new FOC of 11.9?

Does 1.2% difference between 125 and 140 seem a little low?
Is the diff. in calcs due to one acually measureing the broadhead length?

[Fletchead]

1.2% sounds about right for 15 grns. Yes to the second question. F.O.C. charts dont take into account b.h. length because of thw vast difference in designs and length differences. If your going from a 125 Muzzy to a 140 Muzzy you should be pretty close on your figures.

[nub]

Thanks Fletchead, just seemed a tad low for adding 15 gr. to me. Acually I' m wanting to try the 140gr. G5 Montec. I' m not real sure how long this head is compared to a Muzzy. I' d think they wouldn' t be that far appart lengthwise.

On a side question, anyone know approx speed loss for an additional 4" feather and 15 more gr. of broadhead? 10 fps?

[littleal]

10fps
Man we' ll have time to light a smoke and pop open a brew while waiting for the arrow to hit the MOOSE!
JK pal
AL