jonnyslim

Hey guys, just wondering what i could do to increase my FOC from about 7.6 to somewhere between 10 and 13. Right now im shooting 100 gr. heads and am thinking about upping the ante to 125 gr. heads, any ideas on how much higher my FOC will get by switching up? Also i heard that switching to lower weight vanes like blazers may help as well?


Opinions?

Arthur P

Adding weight to the front end of the arrow and/or reducing weight on the tail end does increase your FOC, so changing to lighter vanes will help. Switching to feathers would do a lot more because they are much lighter than even the lightest vanes.

Changing to 125 gn tips should jack your FOC up to around 10%. If you want more FOC, then add more weight up front or lighten the load in the rear.

Dr. Ed Ashby is doing a new arrow lethality study on Asian buffalo in Australia. It's still in it's early stages because the study is going to run for several more years but some of his early findings are interesting. Such as arrows with extremely high FOC (20% +) are showing significantly better penetration than arrows with more normal FOC's.

ijimmy

Take your nock off , put some epoxie on a splitshot sinker and drop it in the arrow , that will do it , but changing your foc will change otter things allso , like spine , and point of impact ,and trajectory

A heavyer head , and lighter tail [read feathers] will do the same



Very intresting ,I know he advocates 2 blade fixed heads allso . The bows and arrows required for buffalo , and african game , are putting out some serious energy , that Im sure is relative to the equasion

jonnyslim

Thanks for all your ideas guys. i think i will be looking at some different vane/feather options as well as starting to shoot 125 grs broadheads. Hey IJIMMY, were you kidding about the split shot?

Straightarrow

Doesn't surprise me in the least. I've been advocating high FOC for years, (along with guys like you) yet most seem happy to get to the lower end of the acceptable range. When using carbon arrows, it's pretty easy to get a high FOC and still have a relatively light arrow.

I've suspected that FOC's used by most hunters was too low in the past several years. I see so many hunting videos of deer being shot with high speed bows, and very little penetration, and all from hunters who suposedly know what they're doing! I've blamed it on the 3D mentality. What's good for 3D, is not necessarily good for hunting.

ijimmy

Ya just kidding , but it would work

Chupacabras

At 20 yards there is not much difference in point of impact between a 125 grain vs 150 grain tip. Beman has an arrow that is half camo/ half black carbon. It is made to have a higher FOC.

jonnyslim

So just curious when i picked my arrows i had them spined for 100gr. heads. According to the chart i would still use the same size arrow for 125gr. heads. So how much different in spine could there be if i make the switch?

Bulzeye

You could always use 125s in the front, and helical feathers in the back for lighter reaer weight and just enough drag to help teh heavier head do it's dirty work.

Arthur P

No way to tell without even knowing what kind of arrows you're talking about. Go to www.bowjackson.com and click on the Arrow FOC and Weight link. Choose the brand of arrows you've got, then just plug in your numbers. It probably won't be exact, but it'll be close. You can use that tool to build all kinds of model arrows - see what'll happen to your weight and FOC if you switch from 85 gn points to 125 gns, or from 4" vanes to 5" feathers... all kinds of different combinations.