FOC importance

[DoubleLunger]

Hey all. I'm currently working on my current setup in preparation for Namibia next fall and was wondering how important it is to be concerned with FOC%.
I've used a couple different online calculators and formulas and ended up with only an 11% FOC.
I'm shooting a 440 grain arrow with 70pounds draw weight at 269 feet per second.
On my list is Kudu, Gemsbok, Zebra, Warthog.
So yeah, just wondering if I should be worried about my lower FOC or if my setup will be just fine.
Thanks fellow bow hunters

 

[Fire652]

Foc will stabilize an arrow at longer distances giving you increased accuracy. Think about a baseball with a string attached. When thrown the ball pulls the string through the air. However you can go to high on foc as well. I have heard reccomendations of 10 - 17. I have found my bow shoots well at 16 percent foc. If your arrow shoots well and you have great groups at all ranges you hope to shoot then you are fine.

 

[Fire652]

If you want to mess with it a bit you can always go with a higher weight broadhead as well

 

[mrpoindexter]

My plains game bow specs from my last safari (not at home and had to find my notes online on another forum):

407 grain arrow, 12.23% FOC, 259 FPS for roughly 61.0 Ft-Lbs KE, 0.469 Momentum

Compared to you shooting 11% FOC, 269 FPS for 70.6 Ft-Lbs KE, 0.525 Momentum

I had a pass through on my Kudu, did not pass through either zebra I shot (and I lost one of them.) I did not shoot a gemsbok or warthog.

I did switch to a heavier bow for plains game because of the lack of pass throughs and disappointing penetration on the zebra and also blue wildebeest (had to get a PH kill on that one) and the eland (good bow kill but would have liked better penetration). Nyala, impala and bushbucks were pass throughs. These were all with fixed 3 blade broadheads.

I have also looked at moving up my FOC on my dangerous game rig and am now at 30% FOC in preparation for my elephant hunt. I think by far, heavy arrows, high FOC is the best insurance for when you hit a bone. I went through the video of my zebra and wildebeest shots and there were right on the money. The wildebeest hit was perfect. It just didn't punch through. My first zebra shot was also a perfect placement but just didn't get in far enough - likely from hitting a rib and not having the oomph to push through it.

Even with a heavier arrow, I am plenty fast enough to get the animals. I would like to have more momentum and a higher FOC. I have strongly considered increasing my FOC to 15-20% and pushing up my arrow weight to 500gn+. I know for the smallest animals, that is crazy overkill, but I am not so concerned about impala or blesbuck. I don't want to chase a black wildebeest across the country and I would rather put two holes in every single animal even if I hit a rib or two. I basically spent $1200 on a single animal I lost. That is more than I will spend on better arrows/broadheads.

That said, I expect you will be fine with your setup. It was better than mine in arrow weight, KE and momentum. Your FOC is close to what mine was. You probably won't have a problem. My issue is that probably is not the same as won't. Not only did I lose an animal, I lost an entire day of hunting tracking the damn thing. I could well have shot another animal in that time (and saved the fee on my second zebra).

If you are open to the possibility of taking what Africa gives you, there may well be a wildebeest that crosses your path. They are tough as hell - they don't call them a poor man's buffalo for nothing. If I saw one and was in a blind with my bow I had for PG and my dangerous game bow, I would grab the dangerous game bow because I wouldn't trust the lighter bow/arrow combo to guarantee a kill shot. Just my $0.02.

 

[firehuntfish]

Hey all. I'm currently working on my current setup in preparation for Namibia next fall and was wondering how important it is to be concerned with FOC%.
I've used a couple different online calculators and formulas and ended up with only an 11% FOC.
I'm shooting a 440 grain arrow with 70pounds draw weight at 269 feet per second.
On my list is Kudu, Gemsbok, Zebra, Warthog.
So yeah, just wondering if I should be worried about my lower FOC or if my setup will be just fine.

The answers you seek were already kind of addressed in another thread here. Sooooo many variables play a role in the effectiveness of your bow & arrow combination that it's hard to point to any single factor being the most important. That said, FOC is definitely up there in my experience. The way we need to think about the physics of the mystical flight of the arrow has changed. We have now learned that momentum is the best indicator of penetration.... Not speed... FOC and total arrow weight are two main contributors to momentum....The downside to a higher total arrow weight is a slower arrow. The trick is to find the effective balance for both.

For your arrow as an example at 440 grains, in theory you can build an arrow to achieve approximately the same total arrow weight and drastically increase your FOC. You can throw all of the archery calculators and theories on arrow flight and physics out the window.... Two tests are indisputable... The first being if 2 arrows of the exact same total weight with the same broadhead or field point, are shot from the same bow, with the only difference being that one arrow has 10% FOC and the other arrow has 25% FOC, the higher FOC arrow will significantly out-penetrate the lower FOC every single time.....

The second test shows that any well-tuned arrow of let's say 400 grains as an example, will not penetrate nearly as well as a similarly tuned arrow of 600 grains, regardless of the FOC. Now combine the total arrow weight with a significantly higher FOC, and you combine two very powerful variables that determine penetration. Without getting too technical, I think you can see what I'm getting at... So, to answer you question in simple terms.... Assuming that you are using strong fixed blade broadheads and you put the arrow in the right spot, your current set-up should work well enough for most plainsgame. Would it hurt to increase your total arrow weight and FOC?? Absolutely not... To paraphrase Dr. Ashby, "nobody ever lost an animal because of too much arrow penetration."

Good luck and have fun on your safari!

 

[DoubleLunger]

If you want to mess with it a bit you can always go with a higher weight broadhead as well

This makes perfect sense. Thank you

 

[DoubleLunger]

My plains game bow specs from my last safari (not at home and had to find my notes online on another forum):

407 grain arrow, 12.23% FOC, 259 FPS for roughly 61.0 Ft-Lbs KE, 0.469 Momentum

Compared to you shooting 11% FOC, 269 FPS for 70.6 Ft-Lbs KE, 0.525 Momentum

I had a pass through on my Kudu, did not pass through either zebra I shot (and I lost one of them.) I did not shoot a gemsbok or warthog.

I did switch to a heavier bow for plains game because of the lack of pass throughs and disappointing penetration on the zebra and also blue wildebeest (had to get a PH kill on that one) and the eland (good bow kill but would have liked better penetration). Nyala, impala and bushbucks were pass throughs. These were all with fixed 3 blade broadheads.

I have also looked at moving up my FOC on my dangerous game rig and am now at 30% FOC in preparation for my elephant hunt. I think by far, heavy arrows, high FOC is the best insurance for when you hit a bone. I went through the video of my zebra and wildebeest shots and there were right on the money. The wildebeest hit was perfect. It just didn't punch through. My first zebra shot was also a perfect placement but just didn't get in far enough - likely from hitting a rib and not having the oomph to push through it.

Even with a heavier arrow, I am plenty fast enough to get the animals. I would like to have more momentum and a higher FOC. I have strongly considered increasing my FOC to 15-20% and pushing up my arrow weight to 500gn+. I know for the smallest animals, that is crazy overkill, but I am not so concerned about impala or blesbuck. I don't want to chase a black wildebeest across the country and I would rather put two holes in every single animal even if I hit a rib or two. I basically spent $1200 on a single animal I lost. That is more than I will spend on better arrows/broadheads.

That said, I expect you will be fine with your setup. It was better than mine in arrow weight, KE and momentum. Your FOC is close to what mine was. You probably won't have a problem. My issue is that probably is not the same as won't. Not only did I lose an animal, I lost an entire day of hunting tracking the damn thing. I could well have shot another animal in that time (and saved the fee on my second zebra).

If you are open to the possibility of taking what Africa gives you, there may well be a wildebeest that crosses your path. They are tough as hell - they don't call them a poor man's buffalo for nothing. If I saw one and was in a blind with my bow I had for PG and my dangerous game bow, I would grab the dangerous game bow because I wouldn't trust the lighter bow/arrow combo to guarantee a kill shot. Just my $0.02.

Wounding an animal is of course the last thing I want to do. Furthermore, I would also much rather see a pass through on a wildebeest instead of questioning myself on the arrow doing its job. It's almost sounds like I'm right on the fence of being in the "ok" and being just a little light for Zebra, Kudu, wildebeest, etc

Thanks for the insight. Definitely helpful. Good luck out there and happy hunting

 

[DoubleLunger]

My plains game bow specs from my last safari (not at home and had to find my notes online on another forum):

407 grain arrow, 12.23% FOC, 259 FPS for roughly 61.0 Ft-Lbs KE, 0.469 Momentum

Compared to you shooting 11% FOC, 269 FPS for 70.6 Ft-Lbs KE, 0.525 Momentum

I had a pass through on my Kudu, did not pass through either zebra I shot (and I lost one of them.) I did not shoot a gemsbok or warthog.

I did switch to a heavier bow for plains game because of the lack of pass throughs and disappointing penetration on the zebra and also blue wildebeest (had to get a PH kill on that one) and the eland (good bow kill but would have liked better penetration). Nyala, impala and bushbucks were pass throughs. These were all with fixed 3 blade broadheads.

I have also looked at moving up my FOC on my dangerous game rig and am now at 30% FOC in preparation for my elephant hunt. I think by far, heavy arrows, high FOC is the best insurance for when you hit a bone. I went through the video of my zebra and wildebeest shots and there were right on the money. The wildebeest hit was perfect. It just didn't punch through. My first zebra shot was also a perfect placement but just didn't get in far enough - likely from hitting a rib and not having the oomph to push through it.

Even with a heavier arrow, I am plenty fast enough to get the animals. I would like to have more momentum and a higher FOC. I have strongly considered increasing my FOC to 15-20% and pushing up my arrow weight to 500gn+. I know for the smallest animals, that is crazy overkill, but I am not so concerned about impala or blesbuck. I don't want to chase a black wildebeest across the country and I would rather put two holes in every single animal even if I hit a rib or two. I basically spent $1200 on a single animal I lost. That is more than I will spend on better arrows/broadheads.

That said, I expect you will be fine with your setup. It was better than mine in arrow weight, KE and momentum. Your FOC is close to what mine was. You probably won't have a problem. My issue is that probably is not the same as won't. Not only did I lose an animal, I lost an entire day of hunting tracking the damn thing. I could well have shot another animal in that time (and saved the fee on my second zebra).

If you are open to the possibility of taking what Africa gives you, there may well be a wildebeest that crosses your path. They are tough as hell - they don't call them a poor man's buffalo for nothing. If I saw one and was in a blind with my bow I had for PG and my dangerous game bow, I would grab the dangerous game bow because I wouldn't trust the lighter bow/arrow combo to guarantee a kill shot. Just my $0.02.

Btw where do you think your arrow hit on the Zebra that you hit but couldn't be recovered?

 

[DoubleLunger]

The answers you seek were already kind of addressed in another thread here. Sooooo many variables play a role in the effectiveness of your bow & arrow combination that it's hard to point to any single factor being the most important. That said, FOC is definitely up there in my experience. The way we need to think about the physics of the mystical flight of the arrow has changed. We have now learned that momentum is the best indicator of penetration.... Not speed... FOC and total arrow weight are two main contributors to momentum....The downside to a higher total arrow weight is a slower arrow. The trick is to find the effective balance for both.

For your arrow as an example at 440 grains, in theory you can build an arrow to achieve approximately the same total arrow weight and drastically increase your FOC. You can throw all of the archery calculators and theories on arrow flight and physics out the window.... Two tests are indisputable... The first being if 2 arrows of the exact same total weight with the same broadhead or field point, are shot from the same bow, with the only difference being that one arrow has 10% FOC and the other arrow has 25% FOC, the higher FOC arrow will significantly out-penetrate the lower FOC every single time.....

The second test shows that any well-tuned arrow of let's say 400 grains as an example, will not penetrate nearly as well as a similarly tuned arrow of 600 grains, regardless of the FOC. Now combine the total arrow weight with a significantly higher FOC, and you combine two very powerful variables that determine penetration. Without getting too technical, I think you can see what I'm getting at... So, to answer you question in simple terms.... Assuming that you are using strong fixed blade broadheads and you put the arrow in the right spot, your current set-up should work well enough for most plainsgame. Would it hurt to increase your total arrow weight and FOC?? Absolutely not... To paraphrase Dr. Ashby, "nobody ever lost an animal because of too much arrow penetration."

Good luck and have fun on your safari!

Makes sense. Thank you and happy hunting

 

[htx519]

I would agree that shot placement and arrow penetration are the two most important factors in getting short blood trails and quick recoveries. It has been our experience that our bow hunting guests who use sturdy fixed-blade broadheads shooting heavier arrows get much better penetration results even with lighter poundage bows.

We have a female client who has hunted with us many times that comes to mind. She shoots a 50lb compound bow with a 650 grain arrow and a 2-blade fixed broadhead. She gets more pass-thrus than most men shooting much faster bows with lighter arrows.

 

[mrpoindexter]

Btw where do you think your arrow hit on the Zebra that you hit but couldn't be recovered?

I hit my lost zebra right on the top of the leg where the pattern creates a ^ shape. He took off like Seabiscuit and my PH told me it was a good hit. We could see the blood coming out as he ran off and had a good blood trail for a bit but it dried up. As I was in an elevated blind, the trajectory was down and I guess the blood stayed in him. My best guess is a rib prevented my arrow from penetrating deep enough for a quick kill. He likely died somewhere that we couldn't find. We never saw him for the next 6 1/2 days.

 

[DoubleLunger]

I would agree that shot placement and arrow penetration are the two most important factors in getting short blood trails and quick recoveries. It has been our experience that our bow hunting guests who use sturdy fixed-blade broadheads shooting heavier arrows get much better penetration results even with lighter poundage bows.

We have a female client who has hunted with us many times that comes to mind. She shoots a 50lb compound bow with a 650 grain arrow and a 2-blade fixed broadhead. She gets more pass-thrus than most men shooting much faster bows with lighter arrows.

I'm considering upgrading to a 499 grain arrow with a fixed two blade 125 grain broadhead with a 40 grain outsert. According to an online calculator my KE will only go from 70 to 68 ft-lb

 

[DoubleLunger]

I hit my lost zebra right on the top of the leg where the pattern creates a ^ shape. He took off like Seabiscuit and my PH told me it was a good hit. We could see the blood coming out as he ran off and had a good blood trail for a bit but it dried up. As I was in an elevated blind, the trajectory was down and I guess the blood stayed in him. My best guess is a rib prevented my arrow from penetrating deep enough for a quick kill. He likely died somewhere that we couldn't find. We never saw him for the next 6 1/2 days.

That sounds like something that I rather not have to go through

 

[mrpoindexter]

The online calculators give very erroneous data when putting in higher arrow weights and using their speed estimators. I have found SFA from pinwheel to be accurate but that is a downloaded program , not an onload web page.

Generally, the online calculators all underestimate the actual speed when using a heavier arrrow and so they state your KE goes down when it will actually go up. That also causes them to underestimate the new arrow momentum as well.

 

[DoubleLunger]

The online calculators give very erroneous data when putting in higher arrow weights and using their speed estimators. I have found SFA from pinwheel to be accurate but that is a downloaded program , not an onload web page.

Generally, the online calculators all underestimate the actual speed when using a heavier arrrow and so they state your KE goes down when it will actually go up. That also causes them to underestimate the new arrow momentum as well.

No surprise there. Never trust the internet

 

[firehuntfish]

I'm considering upgrading to a 499 grain arrow with a fixed two blade 125 grain broadhead with a 40 grain outsert. According to an online calculator my KE will only go from 70 to 68 ft-lb

Forget about what the calculators say.... A 500 grain arrow with 20% FOC or greater will get you much better penetration for sure...

Keep in mind that when you change the balance point and overall weight of the arrow, you are affecting the spine. A heavier arrow with more FOC is only better if it is flying in tune. You might need to go up in spine or adjust your draw weight. Shoot a few of the heavier arrows through paper to see if you are getting near true flight.