Erratic BH flight between bows

[XB I GO]

This is weird to me but maybe there's an explanation or something that can be done about it. When I put a certain broadhead on a Quill and send it from the Mag340 it flies straight, consistent and accurately. Same broadhead on a BEZS out of the M380 throws it extremely low and left with a huge spread. The broadhead is a 125 grain fixed 3-blade. For reference, both the Mag 340 and M380 shoot field tips, expendables and other fixed blade interchangeably. This is the only broadhead I've had this happen with? I don't think the brand/model matters here, If it flies right from one, why not the other?

[Boo]

The faster the bow, the more broadhead alignment and tiller can affect flight. Broadhead alignment can go out after hitting a target.
https://youtu.be/__duPM7CfrA?si=ZPhX81KhI6bEq17Q

[Hi5]

By all means confirm broadhead alignment, as Boo suggests.

If broadhead alignment is not an issue, you may have a different problem. I suspect that no two bows have perfectly the same limb thrust or limb alignment to the frame. If one bow has a dominant left limb, you may tune it to shoot well on a target. Shoot the same arrow from a bow that has perfect balance between limbs, or right limb dominance, it'll shoot differently.

[robertyb]

Also the ZS is a lot stiffer than the Quill which might be causing the problem. Shoot the Quill through the 380 and see if it flies the same.

[nchunterkw]

As Boo suggested earlier…the faster bow and stiffer arrow are highlighting some BH alignment issues I suspect. If it’s the BH I think…. Make sure the individual blades don’t have any bends…..especially the very tip of the blade. A smal curled over tip could cause havoc at the higher speed. Also just work with 1 arrow at a time.

[xcaliber]

Well I have found that the faster the bow is the more you will notice any inconsistencies in the arrow build, or head alignment. The good news is that you know to test your setup before hunting with it.

[XB I GO]

Well, the M380 with the Quill just throws the bolts all over the place. At least with this BH on a BEZS it is always low/left. Going the other way, the BEZS out of the Mag340, it flies consistently, just hits a different spot than with the Quill. Spin test shows both set-ups are rotating true. I didn't think there was that much difference in velocity. What the one bow has over the other, the other has in less weight of bolt. These are good BH's, I've killed several animals with them from the Mag340. I guess I will reserve them for that bow and just keep on keepin on. Thanks

[Normous]

Usually most Excalibur bows digest most BH and Point combinations well but not always. Your 380 will prefer the stiffer BEZ over the Quills in most cases.

[nchunterkw]

Well, the M380 with the Quill just throws the bolts all over the place. At least with this BH on a BEZS it is always low/left. Going the other way, the BEZS out of the Mag340, it flies consistently, just hits a different spot than with the Quill. Spin test shows both set-ups are rotating true. I didn't think there was that much difference in velocity. What the one bow has over the other, the other has in less weight of bolt. These are good BH's, I've killed several animals with them from the Mag340. I guess I will reserve them for that bow and just keep on keepin on. Thanks

While a crossbow is a bow, you have to think about arrow spine a little differently than with a vert bow. There is no riser to clear and your arrow is pointing directly at the target while in the bow. ( on a vert bow it is pointing a little left for a RH shooter). So in general the stiffer the arrow the better. And as the power of the bow goes up stiffer will generally help. This is what you are seeing with BEZS in the 380. A Quill and a ZS are pretty different in spine so it is not likely they will fly the same. Maybe you could setup your ZS arrows in the 380 and zero it with those then try that in the 340. But in any case if you get a combo to group out of a bow then just zero that group and keep those arrows for that bow.

I only shoot BEZS as they are the stiffest I have seen. And they are good quality. With your bows i think you will find that they will group better than the quills. But if you can group the quills you should be able to use them.

Also, it doesn’t sound like you have a BH alignment problem. It feels to me more like the arrow is just launching differently off the rail. Try each one with a different fletching in the rail. You might see different POI

My 2 cents