Conflicting tuning

[Samdemarais]

That arrow flight video alone may be worth the cost of the app. I've had the Bow Shop Bible app for a while but hadn't actually watched that particular video until just now. The counterintuitive recommended rest adjustments now make perfect sense after seeing what's actually happening in slow motion.

Below is my attempt to illustrate what's going on based on that video and Corey's commentary. Dynamic bending of the arrow shaft also plays a role, which I didn't attempt to include in my illustration. Rest type is also a factor: the longer the arrow and rest are in contact, the more pronounced the effect of misalignment between the rest and string path.
View attachment 266972

That makes some sense, arrow point wants to go towards the power stroke and tail basically kicks off the rest at the end. However , how do you explain why when walk back tuning if your arrows fade to the right as you walk back the correction is to move it left. Seems contradictory.....

 

[Zac]

I've had bows where BH's were right of FP's at 60, and moving the rest right did nothing to fix that, but moving the rest left brought the two together and they came together perfectly. But I've also had to go the other way with bows as well, so I don't get too wrapped up in the charts.

That makes some sense, arrow point wants to go towards the power stroke and tail basically kicks off the rest at the end. However , how do you explain why when walk back tuning if your arrows fade to the right as you walk back the correction is to move it left. Seems contradictory.....

It does, this is the reason I don't walk back tune, goes against the laws of physics. Haven't had anyone that can reasonably give a good explanation. Also Tim G says it's useless.

 

[Mighty Mouse]

That makes some sense, arrow point wants to go towards the power stroke and tail basically kicks off the rest at the end. However , how do you explain why when walk back tuning if your arrows fade to the right as you walk back the correction is to move it left. Seems contradictory.....

I don't use walk back tuning to adjust my rest, but I do agree that the recommended walk back adjustments that I've read seem contradictory to paper/bareshaft/broadhead tuning advice.

I use paper and/or bareshaft tuning to initially set my rest position (and cam lean/position) then verify by comparing broadhead to field point POI. If I notice that my arrows are hitting increasingly further left or right as I get further from the target, I adjust my sight, not my rest.

 

[5MilesBack]

If I notice that my arrows are hitting increasingly further left or right as I get further from the target, I adjust my sight, not my rest.

First off......BS and BH tuning are done as a matter of "relation" between two totally different arrows (bare shaft versus fletched.......and BH tipped versus FP tipped). Whereas WB tuning is solely based on what a single arrow type is doing. You can WB tune with any one of those arrow types however.......BS, fletched FP, or BH, if you wanted to.

I've heard folks say that they just adjust their sight if the arrows hit further left or right as distance increases. Doing that is still going to leave either close range or longer range imperfect. If you start at let's say 7 yards and set your sight perfectly to split a line at that distance, and then you adjust your sight to correct arrows that hit 6" right of that same line at 60.......now your arrows are off that same line at 7 yards. That does nothing to actually change the arrow flight.

I tend to start with a WB tune just to get the arrow at the perfect centershot for that bow and rest combo, and then yoke tune to get BS's and/or BH's aligned with fletched FP's........which has worked very well for me. And for my bows that don't have a yoke.......then I tend to do a WB with only my BH arrows, and in every case my FP's have matched up well as far as windage with the BH's after that.

You've got to figure........when an arrow leaves the bow, it takes just a little bit of time for the fletching to correct for that arrow not coming out of the bow perfectly in line with the powerstroke. By the time it corrects, what line is that arrow on? Is it going to be on the same line of flight at 7 yards as it is at 60? At what point has the fletching fully taken over that arrow to correct the flight? It's interesting to take an arrow by the nock end with the point behind you and throw it as hard as you can down range.......and watch how long it takes for the fletching to take control........and how that arrow flies before and after control is achieved. That arrow will get pretty darn wonky.

 

[Mighty Mouse]

First off......BS and BH tuning are done as a matter of "relation" between two totally different arrows (bare shaft versus fletched.......and BH tipped versus FP tipped). Whereas WB tuning is solely based on what a single arrow type is doing. You can WB tune with any one of those arrow types however.......BS, fletched FP, or BH, if you wanted to.

I've heard folks say that they just adjust their sight if the arrows hit further left or right as distance increases. Doing that is still going to leave either close range or longer range imperfect. If you start at let's say 7 yards and set your sight perfectly to split a line at that distance, and then you adjust your sight to correct arrows that hit 6" right of that same line at 60.......now your arrows are off that same line at 7 yards. That does nothing to actually change the arrow flight.

I tend to start with a WB tune just to get the arrow at the perfect centershot for that bow and rest combo, and then yoke tune to get BS's and/or BH's aligned with fletched FP's........which has worked very well for me. And for my bows that don't have a yoke.......then I tend to do a WB with only my BH arrows, and in every case my FP's have matched up well as far as windage with the BH's after that.

You've got to figure........when an arrow leaves the bow, it takes just a little bit of time for the fletching to correct for that arrow not coming out of the bow perfectly in line with the powerstroke. By the time it corrects, what line is that arrow on? Is it going to be on the same line of flight at 7 yards as it is at 60? At what point has the fletching fully taken over that arrow to correct the flight? It's interesting to take an arrow by the nock end with the point behind you and throw it as hard as you can down range.......and watch how long it takes for the fletching to take control........and how that arrow flies before and after control is achieved. That arrow will get pretty darn wonky.

To each his own, there are many ways to skin this cat.

I use a combination of paper, bareshaft, and broadhead tuning to determine the cam timing/lean/position, rest position, and nocking point location that will give me optimal arrow flight. I like paper tuning because I can do it at close range in my garage after dark or when the weather is bad. I also use bareshaft tuning because paper tears can sometimes be deceiving and I want to confirm that what I'm seeing right out of the bow is truly indicative of downrange flight. Broadheads hitting with field points is the ultimate goal of my tuning efforts, so I use broadhead tuning as final verification. Once I've achieved the same POI (within my shooting abilities) with broadheads and field points (at multiple ranges), I adjust my sight to match wherever the arrows are hitting.

Walk back tuning as I've heard/read it explained—shooting one type of arrow (usually fletched field points) at a succession of yardages using the same point of aim, studying horizontal POI's, then adjusting rest windage to bring all the arrows to the same vertical line—doesn't seem to explicitly tell me that I'm achieving good arrow flight or that my broadheads and field points will hit together. By using rest windage to adjust horizontal POI, I could be taking the bow out of tune to compensate for my sight's second axis being off. Also, the recommended walk back tuning rest adjustments (arrows drifting left = move rest right) seem contradictory to rest adjustments based on paper/bareshaft/broadhead tuning. Perhaps there is a physical explanation for this seeming contradiction, but I personally don't see any reason to incorporate the walk back method into my tuning regimen.

 

[Samdemarais]

I have decided to through it all out the window and just shoot broadheads on my hunting set up and make adjustments until they hit behind my pin when I know I executed a good shot.

 

[5MilesBack]

I personally don't see any reason to incorporate the walk back method into my tuning regimen.

And that's fine, I was just responding to your initial comment about adjusting the sight instead. Before doing any tuning I'd make sure that the 2nd sight axis is set first.

When I do a WB it's more of a "modified" WB. I'll use my top pin to perfectly split the edge of my target face at 7 yards. Then I'll shoot 60 yards and shoot the same edge with my 60 yard pin. If the arrow bisects that edge......great. But if not, I'll bump the rest a hair until it does (we're talking very very small amounts here). Then I start over again at 7 yards and do the same thing.......until the arrow bisects the edge both at 7 yards and 60 yards. The amount of rest adjustment needed is generally so small that it won't even change what you're seeing through paper, but will absolutely bring the close and far arrows to bisect that line.

It would be very interesting to be able to get a high quality video from above.......with a perfectly straight line drawn from the bow to the target and see what the arrow flight looks like in relation to that line........for both an arrow out of a perfectly tuned bow, and the same arrow out of an untuned bow.