Ironwill Broadhead Tuning?

[Marshbanks12]

So I have always shot Ironwill Broadheads and they always fly like darts. I bought a new bow this year and I can't figure out why my broadheads are flying so poorly. First my set up is as follows: A Mathews V3 31 with a 28.5" draw at 70 lbs. Shooting Easton 5mm FMJ's 340 spine that are 27" and 3 fletched with blazer vanes and a wrap underneath. I have a Ironwill 100S up front. Total arrow weight is about 462gr.

My field tips and my mechanical broadheads fly perfectly all the way out to 80 yards and hit the target right where I am aiming.

When I shot my ironwill's today the first shot was at 20 yards....I missed about 18 inches right and into my fence. The second shot was at 8 yards and I hit about 4 inches left of the center. The third and final shot was at 20 yards and now missed 12 inches left into my fence. When shooting at 20yards I could almost see my arrow dancing or knuckling in the air. I basically watched it take a hard right or left off target.

I switched back to field tips and NAP mechanicals and they flew perfectly at 20 yards and 40 yards.

My guess is that I am underspined at 340? I ordered some 300 spine arrows that I am going to 4 fletch rather than 3 fletch hoping that solves the problem? Any other suggestions? Thanks guys!

 

[Mighty Mouse]

An easy way to test if weak spine is the problem would be to turn down your draw weight and see if broadhead flight improves. 340 spine seems about perfect at your specs, so I'd be surprised if underspine is the root cause.

3 Blazers should be enough to steer an Iron Will assuming the vanes are set at 2-3° or more offset/helical angle. Less angle than that could be a problem.

Have you put your Iron Will tipped arrows on a spinner to check for good component alignment/concentricity? FMJ's have a reputation for developing a slight bend after hard impacts.

Have you paper tuned and/or bareshaft tuned your bow?

Have you checked for fletching contact?

 

[Marshbanks12]

The arrows are 3 fletched straight. I don't have any helical. I've spun them and they spin great. Bow is paper tuned great as well.

 

[sutton17]

Check and make sure your have plenty of clearance between the broadhead and shell at full draw.

 

[Evol]

This seems pretty significant. Fletching contact somewhere would be my guess.

 

[GotDraw?]

Have you papertuned?

If not DO IT.

Tuning can change as your string/cables stretch and fixed blade broadheads need a well tuned bow. Impact can change your rest. Whisker biscuits wear out... etc, etc...

Broadheads are less forgiving of bad form:

Is there any possibility that your form has broken down? Improperly flipping your wrist up/down at full draw? Extra fingers touching your release? Inconsistent amounts of nose pressure/direction on string? Inconsistent cheek/jaw anchor? Front shoulder relaxed/down and set? Rear shoulder not relaxed and down? Are you doing the good habit of pre-tensioning your bow grip in your bow hand to "set" into you hand pocket before you come up to draw?

JL

 

[Mighty Mouse]

The arrows are 3 fletched straight. I don't have any helical.

When you say straight, do you mean the vanes are parallel to the arrow shaft? Or that they were fletched using a straight clamp set at an offset angle relative to the shaft? If the vanes truly are straight (parallel to the shaft), that could be part of your problem because they won't be able to induce any rotation of the arrow. Rotation helps stabilize the arrow, and becomes more important with a fixed blade broadhead (compared to a field point or mechanical head). If you have a jig, you could re-fletch a test arrow with 3 Blazers at 2-3° offset and see if that makes the Iron Wills fly better.

 

[nettereo16]

This seems pretty significant. Fletching contact somewhere would be my guess.

Yeah, fletching or BH contact with the shelf. The inconsistent POI for the BHs to me makes me think this is likely.

 

[Evol]

If you have any old arrows with lower profile vanes I'd give them a shot and see. I had an issue with my Hoyt and Blazers getting some cable contact.

 

[Trial153]

Contact issue or slow to drop rest

 

[TX_Diver]

Contact issue or slow to drop rest

Wouldn't a slow to drop rest show up with field points too?

 

[406unltd]

Ya I would have four fletched one arrow with a aae hybrid or something with more weight and better clearance and taken a couple cranks off the limbs and test. As long as no contact is evident it should fly. With that said I do believe the spine change will ultimately give you great results especially since you are moving to four fletch on top of that.

 

[Zac]

I don't think straight fletch exists anymore unless you deliberately fletched them that way yourself. The factory fletched shafts may appear to be straight yet are typically 1 degree. This may seem insufficient but it really isn't considering the height of the vane. As the vane travels vertically off the shaft the one degree angle grows as well. A Blazer induces a good amount of leverage on the shaft due to the height. I've shot Exodus, Ironwill, and Ahnillator with factory fletch with no issues. Made me wonder why I screw around with fletching at all.

 

[Trial153]

Contact issue or slow to drop rest

No where near the same amount. And if it’s slight the fletching will correct it easy enough with a field point. With a fixed head on it your will see call Erratic flight for sure
.

 

[Mighty Mouse]

I don't think straight fletch exists anymore unless you deliberately fletched them that way yourself. The factory fletched shafts may appear to be straight yet are typically 1 degree.

True, but the OP's phrasing makes me suspect he's shooting custom or DIY fletched arrows. I prefer to err on the side of too much rather than too little vane angle, but I agree that 1° offset is probably sufficient and is difficult to differentiate from straight (0°) with the naked eye.

 

[Marshbanks12]

UPDATE:
So I switched from my Bohning Blazer 3 fletch to an AAE Max Stealth 3 fletch and it corrected the crazy flight. It appears my Blazer vanes were hitting the roller guard when executing the shot. The only problem now is that my broadheads are grouping about 8 inches low at 20 yards compared to my field points. Still working on figuring out how to correct this without completely changing my sight.

I am fletching up an AAE Max Stealth 4 fletch right now to see if that maybe adds some more stability.

 

[Mighty Mouse]

The only problem now is that my broadheads are grouping about 8 inches low at 20 yards compared to my field points. Still working on figuring out how to correct this without completely changing my sight.

Adjust cam timing (you'll need a bow press), raise the rest, or lower the D-loop to fix low broadhead point of impact relative to field points.

 

[406unltd]

Bump up rest

 

[WoodBow]

I tend to agree with getting contact somewhere. But your variances sound extreme. Too extreme for form issues, imo. You might try shooting a bareshaft and see what that says.

 

[Not Vegan]

I think a bare shaft will show all.