Frustrating Tuning Process

Doodle30 · #1 08-20-2013, 12:13 PM

In the last few evenings I have been reading a number of the tuning threads on the form and trying to BH tune my bow. Read on here and make reference to a few well respected articles (Easton Tuning) and even referenced Youtube and think you have an easy fix. My seperate groups where good just not hitting with the same point of Inpact, telling me I have a tuning issues. 2 inches right with BH. Easton tells me that is a weak spine reaction.

Then have someone at a well respected bow shop tell you essentially the exact opposite of what you read and hear from others. Different POI no guarnatee of tuning issue. Gang adjust sight and go hunting as long as both groups are fine. BH to the right not an indication of weak spine. Yes I know that everyone with a voice doesn't have something smart to say but I just had some of what I thought where generally accepted principals shot down.

Please be clear, I am not throwing darts any any one person or article. My point is how the heck a guy is supposed know what to believe.

DuckDuckElk! · #2 08-20-2013, 01:09 PM

There is certainly a lot of different material floating around out there regarding tuning. Combining that with forum info and shop info (which can at times be variable in quality) and a guy can have a hard time getting concise direction.

There are a lot of factors that influence the tuning of a bow and specifically the grouping of field points and BH's. Cam lean, tiller, rest adjustment, arrow spine, shooting form all can play a part among other reasons. As you note, BH's hitting right isn't only caused by spine - cam lean and form would be two key factors I'd look at as well. Two inches could be fixed with a hair of an adjustment on the rest as well.

If you want to test the weak spine idea you can try turning down your poundage temporarily, use a lighter broadhead or shorten one of your arrows to test. All would effectively give you a stiffer acting spine. Experiment with small changes to your rest (i.e. 1/16" move to the left).

Anyhoo, 2" at 20 yds isn't bad and it's probably fine to sight in with the BH's... But with a little fiddling you could probably have them hitting the same - sounds like you're close.

Doodle30 · #3 08-20-2013, 01:13 PM

My 2-3 inches was at 60 yeards so I was close and should never had even fiddled with it. Not I have to back track a little to fix me fiddling.

Quote:

Originally Posted by DuckDuckElk!

There is certainly a lot of different material floating around out there regarding tuning. Combining that with forum info and shop info (which can at times be variable in quality) and a guy can have a hard time getting concise direction.

There are a lot of factors that influence the tuning of a bow and specifically the grouping of field points and BH's. Cam lean, tiller, rest adjustment, arrow spine, shooting form all can play a part among other reasons. As you note, BH's hitting right isn't only caused by spine - cam lean and form would be two key factors I'd look at as well. Two inches could be fixed with a hair of an adjustment on the rest as well.

If you want to test the weak spine idea you can try turning down your poundage temporarily, use a lighter broadhead or shorten one of your arrows to test. All would effectively give you a stiffer acting spine. Experiment with small changes to your rest (i.e. 1/16" move to the left).

Anyhoo, 2" at 20 yds isn't bad and it's probably fine to sight in with the BH's... But with a little fiddling you could probably have them hitting the same - sounds like you're close.

L.O.S.T.Arrow · #4 08-20-2013, 01:37 PM

D: Both can be correct pending on perspective...The Easton arrow guide was one of the first guides to help on arrow tuning..its their business...

Regardless of how you tune bare shaft, walkback,or paper tune the rules apply...they all achieve the same goal...

IMHO the paper tune is still the indicator of what that arrow is doing when it leaves your bow...and Easton makes suggestions on how to rectify the issues...

If for example an arrow tears right on a paper test...it can mean a stiff arrow spine...but that issue can be solved by many other adjstments...

]
If an arrow has POI to the right it could tear left and plane right..

Arrow clearance problems can produce false readings also

The simplest way to see if any issues are spine...simply turn bow down [or up] one turn each end of bow and see results it will either fix it, make it worse or have the same result...at least you will know if its a spine issue...

As I wrote in another post the goal for perfect tune is the same POI with broadhead and field point...but not all broadheads are created equal so different results can result with any specific head...

If a broadhead has a POI to the right..however the broadhead flys straight, simply moving the sight may work for the broadheads mark sight for fieldpoints... sometimes one can end up in a rubber room trying to get the same POI...you need access to a press, knowledge and the right equimpment sometimes to achive that...

I have seen rests the react different to the standards such as the Eason guide...like the WB....

things like drop away timing and/or idler wheel lean can play huge factors...one is easy the other needs a press...that is why sometimes simply move sight is a suggestion..

If i can be of any help let me know

JMHO
Neil

Doodle30 · #5 08-20-2013, 02:01 PM

Hi Neil

The next thing I was going to do at the range is turn the bow down but I was so frustrated that I thought it was time to go. Wasn't making any progress.

My bow (Hoyt Rampage XT) was papertuned about two years ago, with the help of a pro shop, but hasn't been since. Not sure how frequently it should be done. BH groups where good but a little right out to 60 yards but I am not one of those guys that sees arrow flight well. I assume that good fixed BH groups out to 60 yards means I am getting good arrow flight. I thought with Paper tuning done an additional BH tune would fix my small issue and it seemed simple enough.

I made note of my settings and went back to default before I left the range.

Now I will shoot a few BH to ensure the groups are still good and then I will gang move the site and be done with it.

All this frustration for a couple of inches. (A clear set-up for someone)

Doodle

Quote:

Originally Posted by L.O.S.T.Arrow

D: Both can be correct pending on perspective...The Easton arrow guide was one of the first guides to help on arrow tuning..its their business...

Regardless of how you tune bare shaft, walkback,or paper tune the rules apply...they all achieve the same goal...

IMHO the paper tune is still the indicator of what that arrow is doing when it leaves your bow...and Easton makes suggestions on how to rectify the issues...

If for example an arrow tears right on a paper test...it can mean a stiff arrow spine...but that issue can be solved by many other adjstments...

]
If an arrow has POI to the right it could tear left and plane right..

Arrow clearance problems can produce false readings also

The simplest way to see if any issues are spine...simply turn bow down [or up] one turn each end of bow and see results it will either fix it, make it worse or have the same result...at least you will know if its a spine issue...

As I wrote in another post the goal for perfect tune is the same POI with broadhead and field point...but not all broadheads are created equal so different results can result with any specific head...

If a broadhead has a POI to the right..however the broadhead flys straight, simply moving the sight may work for the broadheads mark sight for fieldpoints... sometimes one can end up in a rubber room trying to get the same POI...you need access to a press, knowledge and the right equimpment sometimes to achive that...

I have seen rests the react different to the standards such as the Eason guide...like the WB....

things like drop away timing and/or idler wheel lean can play huge factors...one is easy the other needs a press...that is why sometimes simply move sight is a suggestion..

If i can be of any help let me know

JMHO
Neil

DuckDuckElk! · #6 08-20-2013, 03:05 PM

Seems like a lot of drama for 2" difference at 60 yds! Maybe try holding 5 hairs to the left if you think it's a problem... I'm fairly anal about tuning and such, but I'm not sure I'd be picking up on that small a deviation. You must have insane grouping ability - sub MOA accuracy? Seriously though, that speaks well for you come hunting season. I think you're good with where you had it frankly.

Give your rest the tiniest tick to the left and see what happens. Tiny move... thousands of an inch. Quite likely that it may close that gap.

Doodle30 · #7 08-20-2013, 04:56 PM

Yeah I know, but it was so close it seems that it would be an easy fix to obtain perfect POI.

Quote:

Originally Posted by DuckDuckElk!

Seems like a lot of drama for 2" difference at 60 yds! Maybe try holding 5 hairs to the left if you think it's a problem... I'm fairly anal about tuning and such, but I'm not sure I'd be picking up on that small a deviation. You must have insane grouping ability - sub MOA accuracy? Seriously though, that speaks well for you come hunting season. I think you're good with where you had it frankly.

Give your rest the tiniest tick to the left and see what happens. Tiny move... thousands of an inch. Quite likely that it may close that gap.

NBScott · #8 08-21-2013, 03:10 PM

If it was a spine issue it would show up with your field points and your broadheads would it not?

Doodle30 · #9 08-21-2013, 06:21 PM

Quote:

Originally Posted by NBScott

If it was a spine issue it would show up with your field points and your broadheads would it not?

Good question. One to be answered by someone smarter than me.