Broadhead Problem
 

Alright I have asked 3 different archery shops and each one gave me a different answer so I have no idea which to try.

First the problem:

I am trying to get my broadheads to fly the same as my field tips. at 20 yards I am getting them shaft to shaft. So obviously at 20 yards I have no issue. But then I step back to 30.....

Now the field tips are hitting the bulls eye and the broadheads are 6 inches low. I tried moving the rest like I had been doing but they dont get any closer. I am stumped...any ideas?


First diagnosis: "Hmm I have no idea....maybe you should just switch to mechanicals or limit yourself to 20 yard shots."

Second Diagnosis: "Sounds like the broadhead is too heavy, switch to a lighter grain tip."

Third Diagnosis: "its completely natural for the arrow to drop from 20 to 30 yards, just move your pin" (complete idiot) haha I didnt even attempt to explain.

If I were you I would look at getting some better broadheads like G5 strykers they fly more like field tips.But, there is no such broadhead thats going to fly exactly like a field tip.

Well, I agree with your assessment of the different shops. Some pro-shops are just scary. You ought to come to MD, its gets worse the more north you travel.

It sounds like you have ran out of adjustment if you are raised all the way up and still hit low. At this point, nocking point needs to be lowered or you have clearance issues.

Point wieght has no bearing on BH's hitting with field points. Getting some new whiz bang BH out there like G5s that are way overpriced is not your issue, as you seem to know. Just the problem needs to fixed.

Move your nocking point down 1/16" and try again. I start at 20 yards, and then I usually move out to 50 yards.

If you have clearance issues, BH's are going to make it worse. Problems get tougher with clearance issues.

There is no shortage of things that can cause issues like yours.

First, I think a relavant question is what broadhead are you shooting? There are certain heads, such as the crimson talons with curved blades, that have increased surface area. That increase in surface area creates drag, which slows your arrow and causes a difference that is more and more pronounced as range increases. Natural feathers have the same affect, even though they are faster (due to their light weight) right off the bow.

What kind of set up do you have? What poundage, what kind of speed?

I agree with bigcountry. As long as your field points weigh the same as your broadheads, they CAN fly the same (or very close). In your case, I would either move your nocking point down or your rest up a bit. That should bring them close.

I am currently shooting a Hoyt Kobalt set at 47 pounds with a 26 inch draw length.

Muzzy 100Gr. 3-Blade Broadheads and Victory V-force 600 Arrows.


I had the Muzzy's flying great last year with the same set-up besides the arrows. Thats the only thing I have changed. I still have a little more room left to move the rest up some more, so I guess I will continue to try that.

Once that is done I will check the nocking point and go from there. If all else fails and I dont have the thing close by hunting season, I will just sight in for broadheads I guess.

Has the spine changed on the arrows you are shooting now from the ones you were shooting?

I think your arrows might be a little bit weak spined. The Kobalt is a sporty little slingshot and 26 ain't really short for a ladies draw. Someone with OT2 can confirm that... but I'd of opted for 500s.

Take a turn or two off the poundage and see if it changes anything. Back'em off the same... easy to put it right back where it was. And if you have any of your old arrows that worked well sitting around... break'em out and see if they will get right for you. Sounds like you know how to eliminate the variables pretty well... just gotta find whichever one got overlooked. Muzzy's seem to always shoot a little low.... and I have my opinions on why... but its pure speculation. They are a good head, and if you have gotten them to group before I'm sure you can do it again.

I would try and move the rest up...

Hey swamp, you really think weak spined is the issue? I never seen a bad spine cause a huge difference in bh flight vertically.

My OT2 and AA shows this setup being way stiff believe it or not with a 28" shaft. It was closer with 31" shaft. OT2 recommended 1916 shaft. Or something in the .650" spine.

I still do not think that is your problem. That mainly effects left or right point of impact.

I will try all the mentioned theories tomorrow and see how it turns out. I just hate it because its so close to hunting season and I am not ready yet! haha

Is yoru bow arm dead steady during and after the shot? Shoulder down during and after the shot? BH's will bring out a lot of form issues also. If the bow has moved after the release, then that can cause issues too.

Are you resighting in your field points after each movement you make?

I know it's a pain but zero in your FP's after each movement of rest or nocking point then shoot the BH's.

The POI of the FP's wont be that much but the BH's POI will be and you will get a better idea of whats going on.

You are better off with a slightly stiff spine when using BH's.

X2

Great suggestions guys!!!

I would say move your nocking point down just a bit just like BC said. You will be better off than continuing to move your rest up.

Derek

I agree with you BC... it is usually a left to right issue... but here is why I think that...

I had some 400 FMJs that I was shooting off my HCA Iron Mace a couple years ago.... and they constantly wanted to go low and left. When I tried some 340 Axis arrows.... they tuned up nice. Of course a 400 at 70#s off an Iron Mace at 29"... I should of started with a .340 spine. My error.

As you know... a weak spined arrow is going to flex a heck of a lot... and that energy being used to correct flight and have the arrow flex is energy that is NOT going into propelling an arrow... so at least from a common sense standpoint to me... that change or net loss in energy potential for flight is being realized enough at 30 yards to make the arrow drop lower.

I have seen improperly spined arrows do lots of weird things off compound bows with release aids.... I've seen them kick and shoot in all directions. There are just so many variables that if we can eliminate a couple at a time it will get us much closer to the real cause of the problem.

Read this after writing the last reply. I suppose that fixes that problem. Thats suprising to me. 26" is fairly short for an arrow shaft even if it is long of average for a female shooter. Oh well... worth a try and a look anyway.

good idea....noone recomended that, but then she will also more than likely have to change her knocking point as well, wich really isnt that big of a deal.

BC,
I agree for the most part, except she's shooting a SLOW BOW, and at 50yds, she's be throwing stuff in the dirt.

Keep moving the rest or nockpoint, and see where that gets you. If you have room, go a full 1/8" and see where you're at. If that overcorrect, then work backwards 1/32" at a time. I can be quite frustrating, I agree, and with your FOC (15%) you may actually have hit the point where you have too much FOC for that set-up.



Actually SC, she's a good bit overspined, and the only fix might be more tip weight, but then her FOC is gonna go from 15% to 18%, which may just worsen the problem.

Jenna,
With your numbers on OT2, I'm seeing that if you go with a 28.5" arrow and a .650 spine arrow, you would be about right keeping the 100gr tip, or you could go with a .700 series and a 75 gr tip, still have 10% FOC, and see what that does for you. I'm thinking with that set-up, you may continue to have the issue, even though you're adjusting things because the FOC is so high. And with your arrow speeds (200fps or so) the spine may not make too much of a difference, you might be able to try a 75gr tip and see what happens. Dropping down to a 75gr tip gets your FOC around 11%, even though it makes the spine stiffer, it still may help, because stiff spine issues generally are left - right problems not diving arrows.

Good Luck with it, I hope some of that rambling helps.

And don't sweat it too much, you still have a good bit of time, and some decent people to bounce questions off of. Not to be negative or anything, but I don't honestly think I'd take a shot past 20yds with your set-up, but it's still frustrating to not have things as well tuned as you'd like.

That I highly doubt, The higher the FOC the better arrow flight and penetration, I have tested arrows up to 34% FOC out of my long bow and compounds and have yet to find the point where I have too much FOC.

No going to 18% will help some, but untill it gets to over 19% most people are not going to see any difference and those differences are a huge benefit to flight and penetration.

Not doubting you Kanga, but at what velocities where the compounds shooting at (I'd have to go awfully heavy to slow my set-up down to 190fps, say like 700gr or so)??? She's probably only shooting 185-190fps, and there may be a BIG drop off after 20yds. I agree she may be able to get things together, but it may be a little easier with an FOC of 10% or so than 15%, especially using Carbons, and especially at these speeds and arrow weights.

I shoot 175fps/630gr and with 20% FOC I can nail a 3d target 0-30yards.

Thats faster than my long bow.:D

Actually the drop off is not that much after 20 yards mainly because momentium comes into play.

A lighter, low FOC arrow is going to lose speed and momentium quicker than a moderately heavy, high FOC arrow. Because the heavier arrow is going to absorb more of the bows energy, plus lowering hand shock, vibration and noise.


Once the arrow has been shot you want the point pulling the shaft instead of the shaft pushing the point, the old saying it is easier to drag a chain is a heck of a lot easier than trying to push it comes to mind.:wink:

I see what your saying, but I'm not sure how well that applies to a 340gr arrow with 15% FOC shot from a compound bow vs. your HEAVY arrow shot from a longbow. I know exactly the argument you make with FOC, I've made it myself, to guys shooting 6-7% FOC arrow and complaining that the WIND blew them off course, while my 12-13% FOC arrows fly just fine. I'm just not sure that out of her set-up especially with a shorter DL that the high FOC arrows are optimal. I could be wrong, and if I am, then I can only say I learned something from it. But it can't hurt anything to drop point weight and see what happens in her situation either, otherwise, she's looking at new arrows to get the spine closer, if nothing else works.

The biggest problem is if she does drop point weight thats going to stiffen the spine, we know at the moment she is over spined, so dropping point weight is only going to add to the problem.

You know, upping the wieght by 5lbs can help the spine greatly.

whats the chances of the new arrows being smaller in diameter than the old ones, and the arrow setting farther down in the prongs of her ripcord rest?

edit.. did some investigating. Her new arrows are .245 vs her old arrows being .285. They are roughly 40 - 50 grains lighter, so that would explain why they were pretty close to being the same spots with fieldpoints.

bigcountry....

would upping the weight possibly help me out? It actually crossed my mind but didnt think anything of it.

I stil havent been able to shoot the darn bow due to the stinkin MONSOON! Hopefully tomorrow the sun decides to stay out for more than 10 minutes.

The thing is, the issue she's seeming to have isn't likely a SPINE issue, I think Josh may have nailed it (see below), but she should still be a bit low at 20, and worse at 30. If the arrow diameter is smaller, she certainly needs to bring the rest up a bit or lower her nockpoint.

Swamp is right. Spine can cause all kinds of issues. I have seen it cause not only windage issues but horizontal (at least on paper). I say give it a try.

Right now I am faced with a tuning issue. I am trying to force a weak shaft to work the way I want it. But looks like I am going to have to try a 75gr head.

Alrighty. I shot some today and I am getting them closer and closer. I think I can possibly get this down with moving the rest. I had to quit cuz my arm was getting tired and I didnt want my shakey arms to mess with my shot haha

So tomorrow is another day! Thanks for everyones help! :biggrin:

Why are you not wanting to move the rest??? If that is what needs to be done to fix the problem, then adjust it a bit, and get it fixed!!!

I think part of the problem (if i understand what she's telling me), is that there is very little verticle adjustment left with the rest. It almost seems like the shop had set the nock point too high to begin with.

I agreee. I am all up for moving the rest believe me haha its the easiest route out of this issue.

Gonna shoot more today when I get time and see if I can knock it out!