Stable Arrow Build

[AKBowGuy]

Alright so here’s the deal, I’m shooting a PSE Nock-On Evo 33, draw weight is around 65 lb. Draw length 28”. My friend and I were tuning it. Started at 10 yards with field tips, two bareshaft, two fletched (4 vanes, small offset, no helical, AAE Max Stealth - .5” x 2.75”) had it shooting fine got it all “tuned up” out to 30 w/ the bareshaft. We added Broadheads to the mix (IW Wide Solid 150) and we’re immediately back to square one. The setup was 25 gr heavier cause I didn’t have 150 gr field tips so it hit a little lower but I was getting a heavy “swirl” in the arrow flight even inside 20. We thought we got it under control so we moved out to 30 with the broadhead and I sent it into my buddies back 40. This was not a fluke. It was so unstable that it hit the ground and bounced over the target into the woods never to be seen again.
TAL: 28.5 in
TAW: 560 gr
FOC 18.5%
100 gr Insert w/ 150 gr IW Wide Solid
Gold Tip Expedition Hunter 340 spine shafts
AAE Max Stealth 4 fletched small offset no helical

Am I underspined, lacking in the fletching department, both or something else entirely?
Thanks y’all.

 

[OctoberGold]

Did you spin the broadhead? Were you shooting multiple broadhead arrows, or just one? If one, it sounds like it was probably the arrow. If multiple, we you seeing any consistency?

 

[Billy Goat]

Just because it's not obviously stated, are you shooting fletched shafts with a broadhead on them?

Or trying to shoot broadheads on a bareshaft?

I assume since you are listing fletching you are shooting them on fletched shafts, just double checking.

Might be a fletching contact issue, what rest are you using?

 

[OR Archer]

A 340 cut that long with 250gr up front out of your bow is under spined in my opinion. You’re compounding the problem with a large broadhead as well.
And when tuning your bow did you shim the cams or just move your rest around? If you’re not shimming the cams you’re not going to get good results

 

[ResearchinStuff]

in addition to those questions, as a point of fact, yes, changing your point weight by 50 grains is enough to change your dynamic spine and produce very different arrow flight, potentially to the point that your arrow is now underspined, especially since broadheads typically need to be a bit stiffer for good flight.

try downloading the free trial of the pinwheel software and seeing what it says about your spine, my guess is it's marginally weak.

4 x AAE max stealth should be plenty of vane area.

Priority actions in order:
1. use the pinwheel spine calculator, if it's grossly weak then take some action to stiffen the spine (new arrows, shorter arrows, less weight up front, more weight in the back)
2. look for vane contact using a field point and fletched arrow
3. try a 100 gr broadhead, see what the results are
4. tune your bow using field points and broadheads of the same weight to get to the same POI.

 

[AKBowGuy]

Just because it's not obviously stated, are you shooting fletched shafts with a broadhead on them?

Or trying to shoot broadheads on a bareshaft?

I assume since you are listing fletching you are shooting them on fletched shafts, just double checking.

Might be a fletching contact issue, what rest are you using?

Yea all the Broadheads were on fletched shafts. They all spun true and I was only shooting one arrow but it was one of the same arrows I had been shooting a field tip on. We saw consistency with the field tip out to 30 and a consistent impact zone with wobbly flight when we put the broadhead on, but only out to 20. Im using a Nock On Elevate 2.0 drop away. It’s an AAE drop away with a Nock On sticker on it.

 

[AKBowGuy]

in addition to those questions, as a point of fact, yes, changing your point weight by 50 grains is enough to change your dynamic spine and produce very different arrow flight, potentially to the point that your arrow is now underspined, especially since broadheads typically need to be a bit stiffer for good flight.

try downloading the free trial of the pinwheel software and seeing what it says about your spine, my guess is it's marginally weak.

4 x AAE max stealth should be plenty of vane area.

Priority actions in order:
1. use the pinwheel spine calculator, if it's grossly weak then take some action to stiffen the spine (new arrows, shorter arrows, less weight up front, more weight in the back)
2. look for vane contact using a field point and fletched arrow
3. try a 100 gr broadhead, see what the results are
4. tune your bow using field points and broadheads of the same weight to get to the same POI.

Sounds good. It was a 25 gr change from a 125 gr FT to a 150 gr BH but still it changes the equation for sure. It could possibly be a vane contact issue. That would explain the randomness of it all. I’ve got some 125 gr mechanicals (SEVR Ti 1.5 125 gr.) that have the same POI as the field tips of the same weight but they both still corkscrew through the air. The only thing we didn’t do was try shimming because we don’t have a bow press.

 

[AKBowGuy]

A 340 cut that long with 250gr up front out of your bow is under spined in my opinion. You’re compounding the problem with a large broadhead as well.
And when tuning your bow did you shim the cams or just move your rest around? If you’re not shimming the cams you’re not going to get good results

We never did shim because we don’t have a bow press. We bareshaft tuned, sight tuned, Rest Tuned and nock tuned. So if there’s an issue I think it must be that I’m underspined, may have a fletching contact issue or I need to shim it.

 

[ResearchinStuff]

All of your arrows corkscrew? With any style point?

 

[Billy Goat]

Yea all the Broadheads were on fletched shafts. They all spun true and I was only shooting one arrow but it was one of the same arrows I had been shooting a field tip on. We saw consistency with the field tip out to 30 and a consistent impact zone with wobbly flight when we put the broadhead on, but only out to 20. Im using a Nock On Elevate 2.0 drop away. It’s an AAE drop away with a Nock On sticker on it.

I think you are underspinned, but it shouldn't be producing the results you are seeing. You want 300 spine for the weight and length you are trying to use.

I suspect you are getting fletching contact somewhere.


Could be as OR said it's just you have moved the rest too far and should be shimming instead, but if you are actually corkscrewing arrows I believe it's from contact.

 

[HandgunHTR]

Are you shooting through paper when you are tuning or you just moving the rest around until you are hitting bareshaft and fletched together?

 

[Marble]

Are you shooting through paper when you are tuning or you just moving the rest around until you are hitting bareshaft and fletched together?

It doesnt sound like there has been any paper tuning at all. Sounds more like sighting in the bow. It needs to be paper tuned at minimum. And the 340 arrow with 250 up front is not going to work.

If it were me I would shoot 300s with enough point weight to get into that 450-500 range, which won't be too much.

And to make those IW wides shoot well that bow need to be very well tuned.

The one rule with archery is "change one thing change everything. "

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[AKBowGuy]

All of your arrows corkscrew? With any style point?

Pretty much. And I’ve done everything I know to do short of shimming. Obviously not as much with the field tip. But yes they all corkscrew.

 

[AKBowGuy]

Are you shooting through paper when you are tuning or you just moving the rest around until you are hitting bareshaft and fletched together?

I don’t have a set up to shoot thru paper so I went to the “pro shop” and shot it through paper there. But once the tuning started I’m sure any progress I made there was lost. Honestly tho I dont think shooting through paper at 5 ft was gunna tell me anything I wanted to know. Wouldn’t it be better to shoot through paper at like 5-10 yards?

 

[ResearchinStuff]

Pretty much. And I’ve done everything I know to do short of shimming. Obviously not as much with the field tip. But yes they all corkscrew.

what exactly is "everything I know to do short of shimming?"

I had to shim my bow on Sunday, but the arrows were never visibly corkscrewing before or after shimming. I also shoot an evolve cam bow, and even when shimming is necessary to have a reasonable centershot, get cables out of contact with the cam, or the arrow running straight across the shelf, there is always a point where the rest can be put that results in acceptable arrow flight.

Visible corkscrew = extremely bad arrow flight

It is not possible to be done with bareshaft tuning and still have corkscrewing arrows, since bareshaft tuning involves shooting a bare and a fletched arrow. If the bareshaft did actually fly straight, but the fletched don't, well there's your answer: fletching contact, like has already been suggested a number of times. Have you checked for that yet? if so, what did you find? Is your rest timed properly? Are your cables making contact? What's your centershot at right now? where's the arrow running relative to the berger hole?

It's also possible that your cams are significantly out of time. Do you have a draw board? if not, how do your cables look relative to the timing marks? Are the cams set to the same draw length mod? Are the draw stops in the same position top and bottom?

Also, your arrows are really weak on spine. They should shoot ok with a field point (i.e. perfectly freaking straight arcs once you're tuned), but they're always going to struggle with broadheads.

 

[Marble]

I don’t have a set up to shoot thru paper so I went to the “pro shop” and shot it through paper there. But once the tuning started I’m sure any progress I made there was lost. Honestly tho I dont think shooting through paper at 5 ft was gunna tell me anything I wanted to know. Wouldn’t it be better to shoot through paper at like 5-10 yards?

The reason why paper is placed fairly close to the arrow is because you want to see which direction the arrow is getting pushed out of the bow. The ultimate goal is to have the string pushing on a straight line from the nock, to the tip of the arrow. This is when you'll get a "bullet hole " in the paper.

After that you need to sight in the bow. Then put a broadhead on and see what happens. You may need some more tuning. Which could be more shimming, a rest movement or a few other methods.

If you have a place to get it in a press, bring it there, shoot it through paper and check to see if it's doing what it should.

A few hours of invested time and maybe some money will eliminate a lot of frustrations and make shooting the bow much more pleasurable.

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[AKBowGuy]

what exactly is "everything I know to do short of shimming?"

I had to shim my bow on Sunday, but the arrows were never visibly corkscrewing before or after shimming. I also shoot an evolve cam bow, and even when shimming is necessary to have a reasonable centershot, get cables out of contact with the cam, or the arrow running straight across the shelf, there is always a point where the rest can be put that results in acceptable arrow flight.

Visible corkscrew = extremely bad arrow flight

It is not possible to be done with bareshaft tuning and still have corkscrewing arrows, since bareshaft tuning involves shooting a bare and a fletched arrow. If the bareshaft did actually fly straight, but the fletched don't, well there's your answer: fletching contact, like has already been suggested a number of times. Have you checked for that yet? if so, what did you find? Is your rest timed properly? Are your cables making contact? What's your centershot at right now? where's the arrow running relative to the berger hole?

It's also possible that your cams are significantly out of time. Do you have a draw board? if not, how do your cables look relative to the timing marks? Are the cams set to the same draw length mod? Are the draw stops in the same position top and bottom?

Also, your arrows are really weak on spine. They should shoot ok with a field point (i.e. perfectly freaking straight arcs once you're tuned), but they're always going to struggle with broadheads.

View attachment 474989

So I know how to sight a bow, I know how to move the rest around to find center point.

I guess I should say this. I know how to get my POI the same (except for with big Broadheads apparently) but I don’t know how to get it to fly straight. I know how to paper tune and understand it’s benefits, but here’s a question, once you’re completely paper tuned, and you go to sight in your bow, you shouldn’t have to move the rest at all after paper tuning correct?

I definitely was starting to think I was underspined. If I kept the same FOC weight and went to an Easton axis 5mm would you recommend 260 or 300 spine?

I think what I need to do is address my arrow spine issue first. Get that to a reasonably solid build and then re-paper tune with bareshafts and fletched shafts. I never thought about that possibility of the vanes hitting the rest or the shelf.

Your paragraph about my “cams being out of time with each other” is out of my knowledge I guess. Draw board and timing marks are not terms familiar with honestly.

I’ll check on the cams now. It would be embarrassing if the draw mods aren’t the same but I guess it’s possible. Like I said I don’t have a bow press so if they’re installed differently from each other I guess it was the previous owner and I just didn’t catch it.

 

[ResearchinStuff]

I think you might really benefit from spending the $30 or whatever to buy the bowshop bible app and walk through the tuning process if you want to do this yourself. Or find someone local who knows what they are doing to help you out, they might even work at your local pro shop.

This shouldn't be too hard to fix in person, but it is more than I am comfortable trying to explain online.

 

[Marble]

So I know how to sight a bow, I know how to move the rest around to find center point.

I guess I should say this. I know how to get my POI the same (except for with big Broadheads apparently) but I don’t know how to get it to fly straight. I know how to paper tune and understand it’s benefits, but here’s a question, once you’re completely paper tuned, and you go to sight in your bow, you shouldn’t have to move the rest at all after paper tuning correct?

I definitely was starting to think I was underspined. If I kept the same FOC weight and went to an Easton axis 5mm would you recommend 260 or 300 spine?

I think what I need to do is address my arrow spine issue first. Get that to a reasonably solid build and then re-paper tune with bareshafts and fletched shafts. I never thought about that possibility of the vanes hitting the rest or the shelf.

Your paragraph about my “cams being out of time with each other” is out of my knowledge I guess. Draw board and timing marks are not terms familiar with honestly.

I’ll check on the cams now. It would be embarrassing if the draw mods aren’t the same but I guess it’s possible. Like I said I don’t have a bow press so if they’re installed differently from each other I guess it was the previous owner and I just didn’t catch it.

There is an established process for all of this stuff with some of it up to debate on what to do at certain points.

A lot of people paper tune bare shafts. It's not 100% necessary but helpful. I do when I can.

Each bow manufacturer has a measurement for where the rest should be. After setting it, yoke tuning or shimming is how to get the arrow coming straight through the powerstroke. After that, very minor rest movements, like less than 1/16 of an inch cam be done.

Don't drink too much of the FOC Kool-aid. Super heavy point weight is a PITA to get to shoot right. 50-75 grains of brass with a 100-125 head is the standard because it works really well.

I've put arrows through shoulder blades and spines. None of them were high FOC or from high poundage bows. Just well weighted arrows with a super sharp broadhead.

Not trying to be bossy just trying to help.

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[AKBowGuy]

I think you might really benefit from spending the $30 or whatever to buy the bowshop bible app and walk through the tuning process if you want to do this yourself. Or find someone local who knows what they are doing to help you out, they might even work at your local pro shop.

This shouldn't be too hard to fix in person, but it is more than I am comfortable trying to explain online.

Yeah probably so. I’ve been hunting with a bow for a while, not all my life but a significant part of it now. But I may have been doing it half way up till now. I’ll look into that bow shop Bible app. Thanx.