arrow spine help

[otis.drum]

i need to weaken my arrows. but how much???

out of my 62# wood lam bow my arrows are hitting 4-5" left of aiming point. they work fine for other bows that are about the same poundage but with a shelf cut to centre. i want to bring them across that 4-5" and so i will have to weaken the spine. currently with 170gr heads, but i have some 220gr heads on order.

does anyone know if this will likely be enough to weaken them, or what might be needed up front to weaken them enough?

the following photo shows how far left my arrows are hitting at 10m (about 4-5"). the shafts are CX350's weighing around 680-700gr. that is 100gr inserts, and 170gr heads. i'm aiming for the round green area to the right of arrows.

thanks

P7140031[1].JPG (44.44 KiB) Viewed 2122 times

[Stickbow Hunter]

the shafts are CX350's weighing around 680-700gr.

I was going to say sand them a bit but after seeing the above I guess you can't do that.

Jeff

[clinton miller]

if the arrows have been cut shorter you could leave them at full length next batch and trim to stiffen them.....if you want to keep using the 170gr. the extra weight of the 220gr heads should make a difference. shoot a bareshaft aswell and note it's relationship with the group.

can you use a thinner side plate to bring them closer to centre??

[otis.drum]

jeff, sanding the carbons could give some troubles hey like explode on impact ....

clint, thinner side plate??? i'm not sure what you mean? i'm shooting round the handle.

the arrows fly dead straight, hit straight and penetrate well so i don't think i need to bareshaft the arrows.

i have no want to stay with this or that weighted heads, just wondering if the extra weighted ones i have on order will be enough to weaken and bring it across that much.

[clinton miller]

i assumed it had a shelf. in which case a thinner strike plate would move the arrow closer to centre, weakening them some. sounds like the only option you have is adding point weight. the extra 50gr should make a difference. the more from centre the arrow sits the more critical the spine has to be.

[TomMcDonald]

jeff, sanding the carbons could give some troubles hey like explode on impact ....

clint, thinner side plate??? i'm not sure what you mean? i'm shooting round the handle.

the arrows fly dead straight, hit straight and penetrate well so i don't think i need to bareshaft the arrows.

i have no want to stay with this or that weighted heads, just wondering if the extra weighted ones i have on order will be enough to weaken and bring it across that much.

With target tips or broadheads?

[otis.drum]

shouldn't make a difference i don't think. i'm talking both.

[TomMcDonald]

shouldn't make a difference i don't think. i'm talking both.

Well it can make a difference so it needs to be given at least a small amount of thought.

[Stephen Georgiou]

try a couple with 5" fletches. It looks like to feathers are 4" is that right?
use 4 feathers instead of three.

Short of that give them to someone with a compound and get some good Oregon / douglas fir arrows. These arrows are tough and last really well with hunting broadheads. I use 170gr tuskers on douglas fir arrows giving me a total weight of 700 grains. These shaft will bare shaft no problems. and hit like trains out of my 73lb bow.

[otis.drum]

thanks stephen,
they are already 5" though.

i have other bows with shelf cut that they shoot perfect from so wont be getting rid of them.

i will see how the extra weight goes with them.

[Stephen Georgiou]

no worries mate.
Carbons are hard to deal with. I found that when I was shooting carbons out of my bear 60lb recurve the 400 spine beaman hawks shot really well but when I increased the tip weight they did not have the same resultant weakening of spine that you would expect from aluminums or woods. I could even shoot 500 spine hawks from the same bow with the same setup with very little difference in the performance. After having similar problems that you are having with the carbons when trying to match some to my 48lb longbow I gave up and went to woods and have had better results.
Cheers