Can broadheads weaken arrow spine?

[kal_mike]

I am in the process of tuning my bow with broadheads and found that they group as well as the field points but to the right. All the books say that groups to the right indicate weak(er) spine. The broadheads add about 3cm to the total arrow length compared to the feild points presumably this weakens the spine? Would this cause the change in impact location?

I have tried three different types of BH (2 two blade and a three blade, all of similar length) all have the same point of impact.

[silent killer]

Mate if the b/head is heavier than the field tip than it will weaken the spine of the arrow as there is more weight to push which means the the arrow will bend more on release.....
......Cheers alex.....

[XTfreak]

Mate if the b/head is heavier than the field tip than it will weaken the spine of the arrow as there is more weight to push which means the the arrow will bend more on release.....
......Cheers alex.....
Huh:confused:???
Ive never heard that one before. Though I do suppose it is true to an extent...
Any weight on the front of an arrow will effect the spine. Just as shortening an arrow will effect the spine.
A heavier broadhead will not have the same point of impact as a lighter field point on the same arrow. This is more due to weight diffence than spine difference...
Bill

[Bowfly]

I noticed in another post you already had you broadheads and fieldpoints hitting the same spot.. Have you changed something recently?
Provided your bow is tuned...Check this out mate
http://www.archerytalk.com/vb/showthread.php?t=539460&referrerid=22477
Rod

[Wareagle]

Huh:confused:???
This is more due to weight diffence than spine difference...
Bill
If that was the case, shouldn't it just hit lower.:rolleyes:

[Bowfly]

I agree Wareagle .. any change to the front of an arrow wether it be weight or length can affect/change spine. Im no pro archer its just something I was taught when setting up my gear.
Rod

[Friar Tuck]

The dynamic spine of the arrow is affected by adding weight to the front or the back of the shaft. More weight at the front weakens the dynamic spine, the back stiffens the spine.

Static spine remains the same because the measurement for spine is based on a set scientific measuring basis.

[XTfreak]

Huh:confused:???
Ive never heard that one before. Though I do suppose it is true to an extent...
Any weight on the front of an arrow will effect the spine. Just as shortening an arrow will effect the spine.
A heavier broadhead will not have the same point of impact as a lighter field point on the same arrow. This is more due to weight diffence than spine difference...
Bill

If that was the case, shouldn't it just hit lower.:rolleyes:
Isnt that what I said???
Bill

[Wareagle]

Isnt that what I said???
Bill
If I misunderstood you, I apologize..
But Kal_Mike broadheads are grouping to the right.....not low.

[jindydiver]

If it can't be corrected by changing the centershot then grouping to the right with broadheads tells us that the spine is too weak. It is not a change in the spine that is causing it, it is plaining of the broadhead that is causing it.
A paper test (bare shaft) will show if his arrows are too soft.

[XTfreak]

If I misunderstood you, I apologize..
But Kal_Mike broadheads are grouping to the right.....not low.
Yes sir I see that now.
It was I that misunderstood, not you.
My apologies to you...
Bill

[kal_mike]

I noticed in another post you already had you broadheads and fieldpoints hitting the same spot.. Have you changed something recently?
Provided your bow is tuned...Check this out mate
http://www.archerytalk.com/vb/showthread.php?t=539460&referrerid=22477
Rod

Yep new bow. Thats a great link, a rest move might be the order of the day. My previous bow only required a nock move too tune the broadheads.

[kal_mike]

Cheers guys. The field point and broadheads are the same weight so no dramas there and they both hit at the same height. The paper tuning of the bow is all sweet and the broadheads group very well so I don't think they are planning. I am going to try moving the rest and/or reducing the draw weight. In the end experimentation is half the fun.