What foc are you using.Just checking.
I jumped to 23% to test Asbby's penitration theory, and i'm impressed..... i added some 5.5 banana feathers on the other end too with an excellent forgiving arrow of 600 grains...Kirk
785 grains....285 up front with 19.5% FOC
15% with Ipe footer POC shatfs and a 160gr BH is the best I can get for a total weight arrow of 625gr. Works for me but I'm not hunting water buffalo either.
12%, historically 12% was considered perfect, the laws of physics haven't changed recently, at least not that I have heard of.
My arrows are 600 grains. I typically shoot 200-225 grains up front and I have seen a noticeable increase in penetration using this set up. This winter I will be playing with 300 grains up front and if my arrows tune well I will probably use that formula for my big game arrows....actually all my arrows. My wife shoots a 500 grain arrow with 200 grains up front. Out of her 45# bow she gets excellent penetration. We both get perfect flight with out setups using arrows with the high FOC.
12% works great on wood and aluminum but the arrows have changed.Years ago trad shooters were not shooting carbon arrows.Carbon arrows recover from the paradox quicker the other types of arrows.So the percentage of FOC for them works better on a higher % then wood or aluminum.Alot depends on the bow,if the carbon is well tuned you can shoot 12% FOC.But they can handle alot higher like 20 to 25% FOC and still shoot good.Probably can't do that with wood or aluminum.I prefer 10 to 12% FOC for wood and aluminum but my carbons like 17 to 20% FOC.Carbon arrows are a whole different learning curve from what alot of guys are use to shooting.
Rick, in studies an arrow with a high FOC will outpenetrate an arrow of the same weight without the high FOC. In other words your arrow with 12% FOC that weighs 600 grains will not penetrate as well as a 600 grain arrow with 23-25% FOC. That is why some arrow makers are building weight forward carbons. Shawn
Read Ashby's latest report....it compares an 82# bow, to a 70# bow with the high FOC.
The 70# came out with 35% more penitration....His next study will be with lower poundage bows from 54# to 70# ...that should be interesting....Kirk
On my Hill bow I use 2117 Legacy with 400+gr up front, I think the FOC is pretty high :bigsmyl: :bigsmyl:
Ok, I am a newbie. Are these studies published somewhere? How can I find them to research this? Thanks
Great article by Ashby on TBM
The only thing that changed is that most carbon shafts are extremely light and ever since they came out, trad guys have been trying to figure out a way to make them work, first they said that they didn't need to be weighted, then they said that weedeater line etc. was the be all end all, then the latest fad is the high foc.. The testing I have seen and done proves only that a high foc carbon is better than a badly weighted one or an unweighted one. It is very easy to add one and one and come up with three, if that is what you wanted to come up with in the first place.
Rick we than can agree to disagree as I do not have any problem tuning carbons or getting the weight where I want it and I have found I do not need as much weight to get better penetration with high FOC and it is not just carbons, it works with wood and aluminum just the same. Have Fun!! Shawn
QuoteOriginally posted by Greg Owen:
Ok, I am a newbie. Are these studies published somewhere? How can I find them to research this? Thanks
top of the page on pow wow
I just went to 300 grain tip and foc of 21, wasnt sure if i went to far,i shoot 56# at 28 arrow length 29.I was trying to up my shaft weight above 600 gr.Shoots great just wanted to make sure that i didnt put to much weight up front, they bare shafted great.
20% foc here with great arrow flight from skinny carbons.
QuoteOriginally posted by longbowben:
What foc are you using.Just checking.
I just grabbed one of my hunting arrows and checked (haven't done that in years). 13%, give or take a tenth.
16% with 200-grain points...pretty happy with this setup...
Greg, Go to the main menu on this forum and click to Dr. Ashby's Reports.