Arrow FOC

[Wind Gypsy]

But, let’s get back to the purpose of the post. I’m not worried about penetration one bit with my setup. Will FOC lead to a more forgiving setup when shooting fixed blade broadheads? I’m not sure that can be proven with anything other than anecdotal evidence and me experimenting with my setup.

Will I see an increase in broadhead forgiviness adding 50-75 grains upfront, and decreasing my speed from 297 to 280’s? The guy at my archery shop says he likes to be in the 290’s for speed, and I won’t see a noticeable difference increasing weight to decrease speed to try to create a more forgiving setup

My take (which isn't worth much when it comes to archery):
In general, going from 297 to 280 FPS is going to make your bow more forgiving just because going fast with fixed blades is not forgiving. Seems common for lots of top level archery guys to build a hunting arrow weight based upon keeping speeds from going much above 280 just to make it a forgiving setup. I'm sure someone on the internet would be happy to credit increased FOC for the increased forgiveness of a slower arrow though.

If your arrows have a stiff enough spine to play nice with the added point weight, I think it's pretty safe to say it will be more forgiving based on speed and also benefit from the increased FOC. Measurably? Hell if I know. If your spine is too weak for the added point weight it wont be helpful.

Have you shared your bow and arrow specs? Usually someone online can run it and show where a program says you're sitting for spine.

 

[ImBillT]

'Tis rare to find such learned interlocuters willing to investigate the minutest of archery minutiae, so I shall take advantage of the opportunity and offer the following theoretical analysis of an arrow's behavior in crosswind—and the effect of FOC thereupon—and solicit the critique of my fellow nerds. @ImBillT I'm particularly interested in your thoughts on my line of reasoning.
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So the best way to get the arrow tip and tail to more closely align with the arrow’s flight path in a high crosswind would be to increase velocity. Yes?

 

[Mighty Mouse]

So the best way to get the arrow tip and tail to more closely align with the arrow’s flight path in a high crosswind would be to increase velocity. Yes?

Yes, that's what my analysis would suggest. Higher velocity would increase drag force in the X direction, which would decrease the angle calculated as atan(FY/FX).

I also think a greater degree of offset/helical angle on the fletching might help keep the arrow flying "straighter" by orienting more of the vane's surface area perpendicular to the flight path and thereby increasing FX. The benefit of more fletching offset might be negated by the competing effect of reduced speed though.

 

[Mighty Mouse]

Will I see an increase in broadhead forgiviness adding 50-75 grains upfront, and decreasing my speed from 297 to 280’s? The guy at my archery shop says he likes to be in the 290’s for speed, and I won’t see a noticeable difference increasing weight to decrease speed to try to create a more forgiving setup

It's also worth taking into consideration that more speed makes an arrow more forgiving of range estimation error. Giving up speed to get more "broadhead forgiveness" comes at the cost of giving up "range forgiveness." Like most things in archery, this decision lies along a continuous spectrum of tradeoffs without a definitive optimal point.

 

[Ought Six]

It's also worth taking into consideration that more speed makes an arrow more forgiving of range estimation error. Giving up speed to get more "broadhead forgiveness" comes at the cost of giving up "range forgiveness." Like most things in archery, this decision lies along a continuous spectrum of tradeoffs without a definitive optimal point.

Oh yeah I definitely enjoy the advantages of speed versus something heavy. I’ve killed quite a few elk and seems like a majority of my shots are 45-65 yards, not having to worry about an exact range at that distance when something happens fast is a nice perk of speed.

My take (which isn't worth much when it comes to archery):
In general, going from 297 to 280 FPS is going to make your bow more forgiving just because going fast with fixed blades is not forgiving. Seems common for lots of top level archery guys to build a hunting arrow weight based upon keeping speeds from going much above 280 just to make it a forgiving setup. I'm sure someone on the internet would be happy to credit increased FOC for the increased forgiveness of a slower arrow though.

If your arrows have a stiff enough spine to play nice with the added point weight, I think it's pretty safe to say it will be more forgiving based on speed and also benefit from the increased FOC. Measurably? Hell if I know. If your spine is too weak for the added point weight it wont be helpful.

Have you shared your bow and arrow specs? Usually someone online can run it and show where a program says you're sitting for spine.

I’m shooting .260’s already, I don’t really want to change arrows that bad as I like what I shoot and they are reasonably priced, I feel that chasing FoC for broadhead forgiveness might decrease my spine to a point where I will lose broadhead tuning ability all together, thus putting me at a worse spot than I already am, not that I’m currently in a bad spot just wanting to mess with things, I was having issues tuning .300’s, not sure how much weight I’d have to put up front to go from .260 to .300 but it’s probably not worth messing with lol. Might just go to a smaller cutting diameter, 2-blade fixed broadhead and see if those are more forgiving, I also always pack expandables in the other half of my quiver which by far are the most forgiving thing out there outside of field tips, but we don’t need to argue about what is better there haha I’ve gone down all those rabbit holes and have field experiences with both on deer and elk

 

[ImBillT]

Oh yeah I definitely enjoy the advantages of speed versus something heavy. I’ve killed quite a few elk and seems like a majority of my shots are 45-65 yards, not having to worry about an exact range at that distance when something happens fast is a nice perk of speed.

I’m shooting .260’s already, I don’t really want to change arrows that bad as I like what I shoot and they are reasonably priced, I feel that chasing FoC for broadhead forgiveness might decrease my spine to a point where I will lose broadhead tuning ability all together, thus putting me at a worse spot than I already am, not that I’m currently in a bad spot just wanting to mess with things, I was having issues tuning .300’s, not sure how much weight I’d have to put up front to go from .260 to .300 but it’s probably not worth messing with lol. Might just go to a smaller cutting diameter, 2-blade fixed broadhead and see if those are more forgiving, I also always pack expandables in the other half of my quiver which by far are the most forgiving thing out there outside of field tips, but we don’t need to argue about what is better there haha I’ve gone down all those rabbit holes and have field experiences with both on deer and elk

You wouldn’t drop spine to increase FOC.

If you wanted to go from .260” spine arrows to .300” spine arrows you would have to drop point weight, not increase it.

You don’t necessarily have to give up speed to get FOC depending on how you get there.

 

[brocksw]

Oh yeah I definitely enjoy the advantages of speed versus something heavy. I’ve killed quite a few elk and seems like a majority of my shots are 45-65 yards, not having to worry about an exact range at that distance when something happens fast is a nice perk of speed.

I’m shooting .260’s already, I don’t really want to change arrows that bad as I like what I shoot and they are reasonably priced, I feel that chasing FoC for broadhead forgiveness might decrease my spine to a point where I will lose broadhead tuning ability all together, thus putting me at a worse spot than I already am, not that I’m currently in a bad spot just wanting to mess with things, I was having issues tuning .300’s, not sure how much weight I’d have to put up front to go from .260 to .300 but it’s probably not worth messing with lol. Might just go to a smaller cutting diameter, 2-blade fixed broadhead and see if those are more forgiving, I also always pack expandables in the other half of my quiver which by far are the most forgiving thing out there outside of field tips, but we don’t need to argue about what is better there haha I’ve gone down all those rabbit holes and have field experiences with both on deer and elk

That 260 spine axis is a great arrow. Tough as hell and tune nicely. If it ain't broke dont fix it.

 

[Ought Six]

You wouldn’t drop spine to increase FOC.

If you wanted to go from .260” spine arrows to .300” spine arrows you would have to drop point weight, not increase it.

You don’t necessarily have to give up speed to get FOC depending on how you get there.

Yeah I don’t think you understood what I said. I understand how point weight affects arrow spine. Increasing FOC on an arrow by increasing point weight decreases the spine of the arrow. I’ve shot .300s with my setup, and they didn’t tune well, .260s tune well, but if I go to increasing the point weight on those .260s chasing FOC, it will decrease the spine, possibly back to the point where it’s hard to tune again.

Seems like my best option is to run with what I’ve got.

The reason I’m looking for forgiveness is I’ve had 2, longer downhill shots, one on a bull elk, and one on a buck of a lifetime. I chose a fixed blade for both shots, and both seemed to “plane high” (for awhile I thought it was fixed blade broadheads fault, but I’ll get to that). On the bull, it shaved the fur off his neck, and I was able to get a follow up with an expandable, similar range, same downhill angle, that hit right where I was aiming, and put him down quickly. The buck I believe survived the shot... Upon further analysis of both situations, I believe poor downhill shooting form is probably to blame for both shots staying high, but I’d prefer to shoot the fixed blades. After it happening twice, I think I need to just practice steep downhill shots more with broadheads and remember to focus on form in the moment of the hunt, but in the moment of the hunt, that’s hard to do sometimes, which is where chasing setup forgiveness comes into play.

Just fun talking about all this stuff too. Thanks for participating everyone.

 

[TheTone]

That 260 spine axis is a great arrow. Tough as hell and tune nicely. If it ain't broke dont fix it.

Axis overall are a great arrow. Decent gpi and a thick wall