Another Broadhead Tuning Question

[CAhunter]

Fellas,
I've been trying to Broadhead tune my bow over the last few nights. My broad heads (trophy taker shuttle T) were consistently hitting about 6" right of my field points in practice at 40 yards. I've been attempting to micro tune my bow by moving my rest (QAD Ultra) very slightly to the left, where my field points were impacting. This brings my broad heads back to center but seems to push my field points further left. I have not been able to bring my Broadhead and field point groups together. I had a new string put on by a reputable shop this winter and also had them tune my bow, and my groups aren't bad and arrow flight seems good. Any suggestions?

 

[Chem-E]

The shop can get the bow close. But you need to tune the bow to yourself for the final micro adjustments. Nobody can do this for you, at least not without you spending time shooting the bow with them. Your draw length, anchor, posture (form), wrist angle, is all unique to you. You will need to make slight adjustments in your draw string length, yoke twists, and maybe micro adj your rest. This can only be done with you shooting the bow in between the micro adjustments.
Just my opinion.

Here is a good link to get you started in the right direction:
http://www.archerytalk.com/vb/showthread.php?t=2128129

 

[doverpack12]

CAhunter, when moving your rest provides no improvement or very little and instead just shifts point of impact of field points and broadheads that is a sign your draw length is a little too long (assuming you are right handed, if you are left handed make the opposite adjustment of everything following aka shorten draw length). This could be 1/8" or 1/2" or more. What too long of a draw length does is positions your release arm elbow at an angle / as viewed from above looking down at the shooter with the target at the top of the page. With your arm in that position that pulls the string into your face and points the broadhead arrow further right when your sight pin says you are on target and you shoot. So the broadhead arrow is flying on a different path to the target than the field point. The reason field points don't have the same resulting impact is because the fletching can overcome the smooth shaft and point and pull then back in line with the tail of the arrow. On a broadhead the tail of the arrow pulls but ends up having to align with the path the broadhead is on. So the fix is to find a way to shorten your draw length in very small increments with some combination of release adjustment, D-loop adjustment, or actual bow settings (mods, string/cable twists or untwists). If you have room to shorten your release even if this will make it shorter than you want try that first just to see if it helps before you go and change your current state of tune on your bow. If you have room to shrink the D-loop that is usually my next place to try. Without knowing what kind of bow and the specs on your setup its hard to say what adjustments to make there. You could also try adding some thickness to the back of the grip (just until you figure out if it really is draw length) but I find that can change your hand position and in turn result in flight issued in itself.

 

[jmez]

Try moving your rest to the right.

 

[forkehornreggie]

When that happens you need to verify that you are not having fletching contact with your rest because if you are then it's pointless until you fix that.

 

[trkyslr]

Fellas,
I've been trying to Broadhead tune my bow over the last few nights. My broad heads (trophy taker shuttle T) were consistently hitting about 6" right of my field points in practice at 40 yards. I've been attempting to micro tune my bow by moving my rest (QAD Ultra) very slightly to the left, where my field points were impacting. This brings my broad heads back to center but seems to push my field points further left. I have not been able to bring my Broadhead and field point groups together. I had a new string put on by a reputable shop this winter and also had them tune my bow, and my groups aren't bad and arrow flight seems good. Any suggestions?

yes,, instead of pushing your rest to the left go to the rt,, I think you'll be suprised. the old easton way of tuning says bh hitting rt move rest left but for some reason thats not always correct. Ive delt with the same issue before and moving my rest the opposite way you would think fixed it

 

[CAhunter]

I shortened my release by 1 adjustment, it feels like it shortened up my draw length and is still comfortable. I sprayed foot powder on my rest and riser/shelf and didn't notice any rub marks so I think my fletching clearance is good. Im shooting a Mathews Switchback rated at 70 lbs (I have it maxed out) with Easton axis 340 arrows cut to 29 3/4" with 100 gr. field points and Shuttle T broad heads. Is the spine of the arrows too weak? Also should the center of your rest, pins, and string align when the bow isn't drawn? Mine don't. My pins appear to be left of the string. Thanks for the help and suggestions,
Brian

 

[doverpack12]

Spine is a non issue. You can try bumping the rest right also. The draw length should fix it for you. There are those strange circumstances where you have to go the opposite way with the rest sometimes though

 

[MNScrambler]

CAhunter, I've dealt with the same issue as you. If I could make one recommendation, it would be to experiment with your grip. Changing where the center of your grip lays in your hand can make some huge differences on broad head impacts. You really need to try and find the most neutral grip as possible. That has been the biggest help for me at least.

 

[CAhunter]

I feel like I'm chasing my tail here. I moved the rest right and ran into fletching contact with my rest. Micro-adjusted left so my fletching wouldn't make contact and had her dialed in to shoot broad heads. Shot a few field points and they grouped six inches left.

 

[doverpack12]

Its grip or draw length. No way to tell without experimenting. The two could be related. The neutral grip left and right is a great suggestion.

 

[Jeff Martin]

This will not be a popular opinion, but you can not always tune your way out of bad broad head flight - and that includes grip, spine, blah blah blah... That is a Myth that gets repeated to often. Anyone that argues with that, just ask Randy Ulmer why he tried to create a mechanical broad head. Anyone think Randy has bad form and can't tune a bow? Why does John Dudley and Levi Morgan shoot mechanicals?

Here is my point: I asked the owner of largest Hoyt dealer in the county what broad head he likes and said "the one that flies with my setup" He went on to say, as a shop owner, he has seen the best of the best broad heads, just not fly in certain setups regardless of tune and shooter. He has 100s of hours testing it. I agree and this is why you have so many guys loving a broad head that the next man says they won't fly. I recently heard Aron on a podcast say the same thing. I have known this for years...it is what it is...

I suggest you figure out your tune for 50 yards via walk back tuning method (which paper tuning is just the start) Google: Maximizing your hunting distance John Dudley. He wrote a great article on this. Once you get it dialed in. Find a broad head that flies good with your rig.

 

[jmez]

Not the time of year to be changing or experimenting with your grip.

What kind of bow are you shooting?

Moving your rest to the sides should not induce fletching contact with the rest? Do you mean contact with the riser?

 

[CAhunter]

Not the time of year to be changing or experimenting with your grip.

What kind of bow are you shooting?

Moving your rest to the sides should not induce fletching contact with the rest? Do you mean contact with the riser?

I am shooting a Mathews Switchback. I feel like I shoot the bow well and get consistent arrow flight with both field points and broad heads, just have not been able to bring the groups together. The Shuttle T's always shoot right of my field points. I made a minor adjustment to my fall away rest moving it right based on a few recommendations on this forum and had fletching contact with the right side of my rest, the solid portion that attaches to the riser, not the fall away arm (I am right handed if that matters). Am I missing something here with broad head tuning? How would an adjustment in any direction for your broad heads not push your field points proportionately if they are not hitting the same spot in the first place?

 

[Jeff Martin]

With a fall away, you have the option to simply turn your noc if you have clearance issues. If you are shooting cock feather up, why not shoot it "cock feather out"? No one says you have to shoot feather down or up on a fall away. I would return it to where it was, turn noc and try again. Have you checked the timing of the fall away? Just because it is falling, it doesn't mean you are not pulling too hard on the cock cord, resulting in rest timing issues. Broadheads highlight issues that field points will not.

 

[doverpack12]

Try shooting with a shorter draw length with either a thicker grip like some cardboard pieces taped to the back for 1/4" thickness and the shorter release adjustment you made earlier. You can also have someone else shoot the bow to see what it does. Not that it matters if they shoot well or not but it will show if its you or the bow. I am a firm believer that you start with a tuned bow and then tune it to the shooter.

 

[Jason Snyder]

My guess is that it's hand torque. When you come to full draw, have someone stand behind you and look at the string coming off the idler wheel. Does it come off perfectly straight, or off to at a bit of an angle?

 

[jmez]

How did you set the centershot? Sounds like that may be off based on a small movement of the rest actually causing fletching contact with the rest body. Sounds like the rest is too far right to start with.

Another simple thing to try is shoot a different brand of broadhead and see if it is flying similar.

Usually in these cases, IMO, yes you are missing something. It usually isn't that complicated. Grip, form and fletching contact issues will most always cause fliers and poor grouping. Unless you have good bad form and do the same things wrong the same way every time. Even if that is the case you should be able to move your groups. You can generally tune around form flaws, as IMO, we all have them. To me that is precisely what tuning is, matching the bow and setup to your particular shooting style and form.

 

[CAhunter]

Today I shortened my release and had a slightly shorter d loop put on. They also adjusted my nock height slightly as they said it was set too high. Went out and shot this evening and after some minor adjustments I believe I'm bringing the two groups together. At fifty yards broad heads still seem to be hitting right of my field points by a few inches but it got too dark to shoot. I'll shoot more tomorrow and see if I can improve it. Thanks for all the help and recommendations. Also, I did shoot another style of broad head (Muzzys) and they shot even further right than the Shuttle T's which I guess makes since, they seem to have more surface area. Thanks again,
Brian

 

[5MilesBack]

Why does John Dudley and Levi Morgan shoot mechanicals? I would hope because they leave large holes and have high confidence in them......not because they can't get the bow tuned to fixed blades.

I suggest you figure out your tune for 50 yards via walk back tuning method (which paper tuning is just the start) Google: Maximizing your hunting distance John Dudley. He wrote a great article on this. Once you get it dialed in. Find a broad head that flies good with your rig.

If it were me, I'd do the walk back tuning with BH's to start with. And then see where your FP's lie.

What kind of fletching are you using? Is it enough to overcome the planing of the blades? I'm not familiar with the Switchback, does it have a yoke? If so, you can yoke tune the impact difference out.