Increasing FOC w/ Broadhead

[Hybridmachine]

I'm changing spine and insert weight this season. Going from 440 to 510. I want as much FOC as possible with the new set up, an the only way I can do this is with a 150 vs 125 broadhead....

What increases should I see between the two...? I've read roughly 2%... I'd like to read your thoughts before I spend the coin on 150's.

Thank You
-Tim

 

[nphunter]

Not sure what your question is? You are changing from a 440 to 500 spine or is that your arrow weight. Too much weight up front will effect your spine also. You can buy brass all thead and epoxy it in behind your inserts to gain FOC also. You are correct on the 2% increase that is close. I just added 40gr up front and gained about 3% FOC.

I would add weights or brass instead of limiting yourself to a very small selection of Broadheads.

 

[Hybridmachine]

What extra FOC will I get with an extra 25 grains upfront...

Total arrow weight as of now is 440g, I am increasing to 510g.... Arrow spine is 300.
2% is not enough for me to change my BH's, well maybe..!
Thanks

 

[Hybridmachine]

What if I cut my arrows 1" longer. Will that make a much of a difference..?

 

[nphunter]

2% or less depending on arrow length, IMO not worth switching to a head that will have more wind drift more than likely.

 

[Brendan]

What extra FOC will I get with an extra 25 grains upfront...

Depends on GPI of the arrow, wraps, vanes, inserts, nocks, all of your components including the length of the arrow. No straight answer.

My opinion - not worth chasing because of the limited selection of heads. If you do want to up FOC, use a 5mm arrow, use 75 grain brass HIT inserts and a footer. If you want more weight, find some interference fit brass screws to epoxy in behind the insert.

I'm going back to 100 grain heads for broadhead selection.

 

[jt4]

Why is going up 25g in broadhead your only option to increase FOC? You can add screw in weights up front, sleeves like iron will makes add 25 grains and add some strength to the front. If you’re changing spine of the arrow your FOC could be completely different even with all the same components.

You could also look at changing to a lighter GPI arrow. The lighter your arrow the more the weight up front actually affects your percentages.


Sent from my iPhone using Tapatalk

 

[roadrunner]

Lengthening your arrow will decrease the FOC from what it could be. Using a heavier insert is better than a heavier broadhead as previously said.

 

[Hybridmachine]

My arrows an components are already on order. Its my best bet with out getting in the 550-600g total weight...

 

[MattB]

IMO FOC is the most over-rated metric related to arrows. Stick with the 125's and toy with heavier inserts if you are insistent, but frankly I wouldn't expend the energy and $.

 

[Brendan]

My arrows an components are already on order. Its my best bet with out getting in the 550-600g total weight...

Total weight can be exactly the same, with more control over tip weight doing it the ways suggested above.

There are disadvantages to going to bigger broadheads - availability and selection, as well as aerodynamics of the head.

 

[jt4]

IMO FOC is the most over-rated metric related to arrows. Stick with the 125's and toy with heavier inserts if you are insistent, but frankly I wouldn't expend the energy and $.

I’m not one of the Dr ashby cult like followers but am curious to why you say it’s overrated


Sent from my iPhone using Tapatalk

 

[GregB]

Gold Tip's website has a FOC calculator.

 

[MattB]

I’m not one of the Dr ashby cult like followers but am curious to why you say it’s overrated


Sent from my iPhone using Tapatalk

Most of the best bowhunters I know don't know - or care - about FOC. Some who profess to (e.g Randy Ulmer) shoot sub 14% as near as I can calculate based on published arrow specs. They all seem to kill animals just fine - lots of them, blissfully ignorant of the internet suggestions to the contrary.

Don't get me wrong in that I dont think it is a bad thing, but it pains me to see folks spend their hard earned money chasing what I believe to be very marginal improvements, and in some cases unwittingly coming up with a less effective set-up in the process.

 

[kodiakfly]

Most of the best bowhunters I know don't know - or care - about FOC. Some who profess to (e.g Randy Ulmer) shoot sub 14% as near as I can calculate based on published arrow specs. They all seem to kill animals just fine - lots of them, blissfully ignorant of the internet suggestions to the contrary.

Don't get me wrong in that I dont think it is a bad thing, but it pains me to see folks spend their hard earned money chasing what I believe to be very marginal improvements, and in some cases unwittingly coming up with a less effective set-up in the process.

Exactly. I mentioned in another thread that we were all killing animals 20 years ago before FOC was “the thing.” I shot A/C/C’s with a 125 head had never even heard of FOC and was blowing through animals. It’s fun to toy with and I did last winter for the first time for fun and to see what the hype was about. I can’t remember what my FOC is now but I did add a brass insert because there is merit in having that weight forward build in an arrow. But people get worried about 14% vs 16% and chase their tails when either arrow likely works fine.

And for me, a little mini-rant; and I certainly don’t mean anyone here or the OP, but I speak generally- I think there’s a tendency nowadays to shoot a deer in the spine or in the ass and blame it on the bow not being tuned, or poor penetration on low FOC...when in reality, they made a bad shot and maybe should’ve practiced more instead of spending all summer repeatedly walk back tuning to 150 yards. It’s easy to say, “man my arrow just didn’t penetrate and that deer got away because my FOC is only 11%...I need 16% to be successful next year!” Maybe it didn’t penetrate because you shot quartering-to, hit the shoulder with a 340gr arrow.

Rant complete. Sorry.


Sent from my iPhone using Tapatalk

 

[Beendare]

Personally I like a big 150gr BH like the VPA or Magnus 150's. I Haven't seen a difference between them and a 125g head...but then I don't shoot really long shots. I haven't seen larger groups drastic wind drift or anything like that. Hold one of those VPA 3 blade 150's in your hand.....they are impressive. They tune/group just like any of the 125's...but of course there is more steel in the working end of your arrow.

I too think chasing high FOC is a waste. From what I've seen with arrow penetration on big critters....its ALL ABOUT arrow weight and perfect arrow flight..........more arrow weight equals more penetration- all else equal. But of course some forum folks don't accept the simple solution.

EFOC; I've been asking for apples to apples data from the Very high FOC guys for decades....all I get is, "Ashby says"-and that he lost his data....maybe his dog ate it. Here he is "Proving" his theory [ha!]..... shooting weighted straws with rubber bands, here [skip to about 10 min]

I do think many of Ashby's tenants of a good hunting arrow are accurate...which is all stuff we have known for years. Where he goes off the rails is his "Bone Threshold", Single bevels and very high FOC. Heck, even the forum guys touting it admit to not shooting it.

 

[Blockcaver]

About 30 some years ago I read the first stuff Ashby put out (maybe in Traditional Bowhunter?). As a registered professional engineer myself, some of his stuff didn’t pass the sniff test. I immediately was s skeptical of his “work” and never followed it.

Meanwhile I’ve kept on successfully bowhunting about everything in NA and some critters in Africa without any issue while shooting normal aluminum arrows for years, then carbon shafts with 100 or 125 gr broadheads of many types. A properly stabilized and good flying arrow with a decent and sharp 3 or 4 blade head and proper shot placement has done it without resorting to “spiral wound channel, bone splitting wonder heads” with high FOC.