tuning- it's a totally random process.

[ozy clint]

yet again i'm frustrated with trying to tune arrows to a new bow. trying to tune axis shafts with 730gr up front out of a 70#@28" border black douglas. i have a 6.75" external footing which reduces the portion of flexible shaft. started out with full length 300's and trimmed. nothing changed, maybe got worse. tried 340's same thing. i'm onto 400's now and seem to be a little better. still some to trim yet. nothing i do makes any difference to arrow flight. i can get them to hit the spot but the tail wags everytime. only seldom does one fly like a dart. i've tried the adcock method but when i get bareshafts and fletched BH's grouping, the BH still flys with a wag. i'm just shooting fletched BH'S now and trim and hope. the strike plate is getting badly worn. i'm shooting 4 fletch so i think i might give 3 fletch, cock feather in a go and see if it is feather contact giving me grief. surely tuning should not take months and months of frustration and still not be tuned. if i could just see a change in flight when i make a change i could work it out myself but changes without change is doing my head in!    really puts me off shooting. "just another session of no progress"

[JC]

G'day Clint! Tuning can be very frustrating and often seems to border on black magic to get it right.

I will have to say following OL's method has yet to fail me but I know others have had problems with it. First of all, I think you are getting false errors if the setup you describe is showing a stiff 300 shaft. On my previous setup using a 300 axis fmj, 450 up front on a 29" shaft tuned great out of a 64#@27" Morrison. Considering the increased weight and poundage, I think you are under gunned with a 300 unless you go very short. I'm 99% sure that 340's are way too soft and would bet lots of money on 400's being wet noodles with that much up front. My "perfect" arrow right now is a 29"  340 axis with 300 head, wrap and 4 fletch out of a 56#@27 Morrison…so I'm relatively confident by that example you are going the wrong way.

Sometimes when an arrow is too weak you get a false reading as the shaft "bounces" off the window. That might be what's happening.

Another thing to consider is if you do get your setup to bareshaft with field points via the OL method, and your fletched arrows with field points fly great, I mean like the preverbal "dart" or "laser", then the issue is not with tuning but with the broad head. Is it perfectly aligned, is it a design that doesn't plane, is the broad head much longer than the field point (yes, this does change the geometry of the arrow)? I have a hard time getting some broad head designs to fly 100% consistently for one reason or another but switched heads and magic, all the problems went away. I've also found on the big wide or heavily weighted heads perfect alignment is critical.

Post a video or pics if you can of your results and you shooting I'll bet there's enough guys on here to help you through it. Don't give up, you CAN get perfect flight with consistent shooting form and proper equipment.    

[robtattoo]

I think Joe's got it right, Oz.
I know my specs are different, but it does confirm JC's thoughts. I'm shooting 66#@31½" & I shoot full length MFX/Axis 340s with a 200gn head. I can't get 300s to fly well without getting ridiculous on head-weight (500gn+) but I can't cut 400s short enough to tune, without dropping to an 80gn head.

70@28 with 730 up front, I would think that a 300 would almost be too weak, even chopped to 29"

I've found, with skinny carbons at least, that changing point weight seems to affect dynamic spine much less than shortening the shaft. For me at least, trimming as little as 1/8 of an inch off makes a noticeable difference. I have a couple of 340s that I've trimmed a ½" from & I have to double my point weight to compensate.

I know you're into chasing critters that chase you back with probable terminal consequences, but were I you, I'd maybe go back to those 300s & try dropping your point weight by a couple hundred grains. You've still got plenty of KE & momentum for buffalo & scrub bulls.

[JRY309]

I agree with JC,sometimes you can get a false reading with carbon arrows.I had some carbons that were showing alittle stiff.They got worse the more weight I added.Thats is a lot of front weight,you may have to try reducing some of the front end weight and see how it reacts.

[overbo]

You sometimes have one fly like darts. That tells me the arro can tune to the bow if your shooting form is a certain way. Instead of chasing arros you may consider reevaluating your shooting form.

[brbowhunter]

I feel your pain oz.. Been down that road before.  I tuned some .600 full length Beaman Classics MFX's with standard inserts and a 125 tip to a 57@28 lb sheepeater recurve.  All "recomended" arrows were too stiff.  With the 600s I get good bullet holes through paper, bare shafts that fly with my fletched arrows, and real pretty arrow flight with broadheads.  

Like the guys above said.  Carbons stiffen up FAST.  If I cut the .600s an inch they then show too stiff and start getting squirrely again.  1/4 inch cuts on carbons.  

All that said some bows/setups just don't follow the normal recoomended guidelines for matching arrows, and yes it is sometimes a really random process.

I have had the best luck paper tuning to match arrows.  I paper tune then check by bareshaft tuning, and then eyballing broadhead flight.  I typically never have to make changes once I get good bullet hole tears through paper.... Good luck..
Man 730 grains up front.  That is a tank!!!

[brbowhunter]

Double nock set?  I could never get good consistent arrow flight until I started tieing double nock sets on my bows....

Just a thought...

[Bldtrailer]

what in the world are hunting      That set up would take out a TREX      

[Bldtrailer]

Running the numbers on Stus millers cal you come up a little weak with a 29 inch arrow.
Playing with longer footing seems to stiffen and or build out you strike plate.
you foc 34.2 with 60 pounds of energy
28 3/4-2811/16 seems to get it right on with stus

[Orion]

Here's something else that might be coming into play.  If you're switching to axis shafts from larger diameter shafts, did you lower your nocking point accordingly?  If not, the arrow could be coming out nock high and you would see a flip.  With enough cant, it might even appear to be a sideways flip.  Just one more thing to check. Good luck.

[Easykeeper]

Tuning can be a royal pain sometimes.  Depending on the center shot of your bow you might want to think about building out the side plate a bit.  I usually shoot ACCs and when I go with the skinnier Axis shaft it's almost like they are sitting to far inside the string.  The Axis shafts are almost at true centershot because of their small diameter, instead of slightly outside the string like a finger shooter needs.  Especially with 730 grain heads...did I read that right...?  

Is it possible that with a 70# bow and that much head weight any carbon shaft will be too weak?

Bare shafts have yet to fail me, but it doesn't mean it isn't frustrating at times, especially when a bow is one the line between spines.  Personally I think your .400 have to be too weak, a 31" .400 is too weak for my recurves that are only in the mid-upper 50# range.  I shoot 31" .340s with up to 250 grain points from my bows so I can't see how a .340 would work for you either.  Honestly, I've never tried to tune anything with that much weight out front so I'm not sure if my experience is even valid in your case.

Good luck, you will get there.

[gringol]

Would a full length footing still be a footing?

[Brianlocal3]

Clint,
I just re-read your "I hate tuning thread" from 2012. Go back to your broadhead and field point way that you did back then.
You will get it brother, you did it before and you will get it again.

[CRS]

I have found the same thing as JC.  You can get false readings, especially with extremes. I would consider a 300 spine arrow with 700 plus grains up front extreme.

I have also found that when dealing with extremes, changing arrow length can have a dramatic impact.

Thusly, if the arrow is the appropriate length I can typically get two different points to fly very well.  For example a 400 spine arrow cut to 30.5 inches out of my 50lb bows typically will shoot 175-200 or 200-225 very well, without a lot of horizontal change of impact.  4-5" in this case.

Whereas an extreme setup can cause 12-18" of horizontal impact movement with a change of weight up front.

[ozy clint]

thanks for the input guys.  So you think 300's are weak. Even with a 6.75" footing? Even with a 30" arrow the flexible portion is only around 24" long. Think of it as a 24" arrow with an 8" point weighing 730gr. That's a short arrow. My draw is 26" so i can trim to about 27". What does bad strike plate wear indicate? I thought it was an overly stiff arrow. I'll try building the plate out. At the moment they are sitting just a little from center.

[L82HUNT]

Originally posted by Easykeeper:
Tuning can be a royal pain sometimes.  Depending on the center shot of your bow you might want to think about building out the side plate a bit.  I usually shoot ACCs and when I go with the skinnier Axis shaft it's almost like they are sitting to far inside the string.  The Axis shafts are almost at true centershot because of their small diameter, instead of slightly outside the string like a finger shooter needs.  Especially with 730 grain heads...did I read that right...?  


Good luck, you will get there.

This is what I'm thinking especially with the border riser which is cut well past center.  Build the side plate out so the arrow tip is just outside of center.

[Josh Perdue]

A bear weather rest made tuning pretty easy for me. I dont know why but my arrows fly like darts since making the switch. Paper tune is perfect when I never could get a perfect tear shooting off the shelf. Broadheads fly perfect as well. That 4$ rest has saved me alot of frustration.