I can't remember the numbers but when I bought my carbon sst arrows I did all the figuring. Just to make sure, what do you go by when looking for broadheads in terms of weight. I think I am shooting 100s but was thinking about dropping down to 85s. I am pulling back 70lbs, my shaft length is 29.5, my arrow weight per inch is 10.5, I can't remember the shaft size, they are 240s but I dont' think that tells the shaft size. The arros size is correct, I am just worried about dropping the bh weight.

Given those numbers I would be very leary of dropping point weight.You are already low on foc and I would probably go with heavier if the dynamic spine would still be ok.

I crunched a few numbers and the 100's are right at 7% foc.This is assuming you have 4" vanes.Feathers would help dramatically.
The 85's would be down around 5 1/2% foc.
125's would be around 9 1/2% foc.


Featherswill increaseyour foc by 2%.


It is reccomended to be between 10%-15% foc for hunting.If you have high ke levels you may be able to go below these parameters a little but I don't reccomend dropping too far below.

Well I haven't been around bowhunting that much so you might as well be speaking Spanish LOL. I think i see what your talking about.

so it would be better to go up in wt if I do anything at all? Correct?

Sorry about that.[&:]

F.O.C is forward of center.Basically this means the percentage of the overall weight that is FORWARD OF CENTER.10-15% will help stabilize arrows in the in flight,wind and during impact it will help with penetration.

Basically if you are shooting 100 grain points with feathers you are fine and don't change.

If you have plasticvanes go to 125 grains and see how the arrows fly because they may weaken the spine. Only in extreme cases would the heavier tip cause a problem but I believe you will like the results.


In no way can I reccomend the 85 grain points.FOR YOUR ARROWS.I have shot 75 grain points for hunting but they gave ME 11% foc.


Was that clearer or am I still overstating it.

ok, so either stay with 100s or go to 125s. But you recommend I might try 125s just to see if there is a major difference?

sorry, I need to mention that I am using veins and not feathers.

Try the 125's.I think you will be happy.

what is so great about bein at 10 to 15 % FOC the arrows i shot last year were about 7 or 8 and they grouped just fine. and i aint go the slightest clue what mine are now and they group extremely well. to me it was just too much work, course noone really told me what the advantages were to havein them in the 10 to 15% range as a possed to somethin else.

It is all relative,what is good or fine to you may not be to me.

Proper foc will yield better arrow flight.
Proper will yield better penetration.
Proper arrow flight will be easier to tune.
Proper foc will haveless affect from wind or objects.
Proper foc will fly and tune better with broadheads.
Proper foc will yield better groups,usually.


With all the above stated,ke,fletching,spine,style of shooting ,etc will play a role.If someone has high ke,the arrow will do better imo with lighter foc than someone with low ke,such as I do.


To give a small example.I tested exact arrows and points that were extremely different in weight.I can't remember but close to 300grains difference.The light arrow at 11% foc penetrated BETTER than the heavy arrow with5% foc.As I increased the point weight on the heavy arrow it did better.The light arrow did better at 11% than it did at 7% or 15%.The arrow was identicall because it was the same arrow,just weighted.The weight didn't affect the spine adversly because the arrow was good from 60# to 100#.


For the record,I pass through deer with NO PROBLEMS.(arrow sticks deep in ground)with 380 grain arrows and expandable broadheads.All with a 58# bow at 28 1/2" draw with a wopping 53-56 ft lb's ke.Fix blade broadheads will hit the same@ 40 yards as field points.I stay with 11% when possible because it works best FOR ME.Some may need something slightly different for optimum but most will be fine between 10-15% as EastonStates.Somecan use less and be fine and some will need more (especially traditional guys).


I really don't mean to overstate foc.It is just another way to get the most but 99% will be well served to try to getfrom 10 -15 and not worry about it.


You asked.

FOC is usually pretty easy. If you just stick with broadheads that weigh at least 100 grains, your FOC will usually be okay. If you use feathers instead of vanes, it'll be even better. If you use 5" vanes or really thick,heavy vanes, you might need to bump up to 125's.

Completely ignore any broadhead that weighs less than 100 gns. Leave those to the Xgames type guys who love tippy-toeing around on the thin edge of sanity.