If you go from 125 to 160 with same length shaft how much spine would you loose ? Thanks
G

Whatch got going on bud?

I am going to Buy some shafts for my old longbow in the am. I was shooting 125 up front and now I want to shoot 160 up front. I was wondering how much in spine do I need to go up. I was shooting 45-50 I dont't know how much you loose when adding another35 gr. up front. Thanks MO.

I am not an athority on this but in my experience I have been able to shoot a wide range of point weight just by increasing or decreasing the thickness of my side plate.  I like to use those felt furniture pads from wal mart.  I think it will in actuality make a difference but I don't know if you or I would really be able to tell much difference in 30 grains.  My bow has enough shelf I can really do a lot with it.  I can shoot atleast anywhere from a 100 grain tip to 175 grain tip on my bow by changing the side plate.

I guess I can't even spell Authority.

This bow is not cut to center..I think I will get50-55 and start out full length and go from there..This is a bow I will just use for target shooting. It has really been a couple of yrs since I shot it but I would like to start. I Think I will pick up a reel for it in the am also.
G

Where you at in MO.?  Good luck bud.

Rolla

Sounds like you are talking about wood arrows also, I am talking about aluminum wonder if they react different?  One of these days I am going to try the wood arrows, kind of seems like a lot of work though but I want to try them.

I still have some 2018 around that I shoot with my striker but mostly carbon now. I do like making woodies...I just hate when they break.

From the books I've read they say 25 grains up front makes the same difference as one inch of shaft length or 5 lbs. of bow weight.Gary

I would play with the dynamic spine calculator to see what the spine rating is for your old arrows, then try and match that with the new head weight.

Disclaimer:

I know nothing about wood shafts, or much of anything else for that matter, but my "thinking face" makes me look like I look like I know what I am talking about!

It's going to depend on how spine sencitive your bow is. My bow will shoot 60-65 or 70-75 woodies.
It's a strong R/D longbow #57@31".
Denny

Geno,  The direct answer to your question is: add 5# for the increase of point weight from 125 to 160.  So If you're now shooting 45-50# spine groups, the next step up will be 50-55#. If everything else stays the same you'll be right there.

Going from 125 to 160, you might be alright with your old spine and you might not, depending on how close you were to start with.  The safe thing is to order the next spine up and cut them an inch long.  You can always shorten them if needed.