Author Topic: Spine help (Read 149 times)

blueslfb · « **on:** February 21, 2011, 09:33:00 PM »

I have a 66' Northern Mist Shelton that is 62@28 and 59lbs at my27" draw. I need help figuring out a starting point for arrows. I have tried several different options but I can't seem to get good flight from anything I have on hand. I have a B50 string on it now and I would like to shoot a 28" to 29" arrow with 160grn points. I also want to stick with woodies. Any info would be great.

Shedrock · « **Reply #1 on:** February 21, 2011, 09:36:00 PM »

I would try 70-75# spine.

Orion · « **Reply #2 on:** February 21, 2011, 10:45:00 PM »

70-75# will probably work, but with a 27-inch draw and dacron string, I think 65-70# or even 60-65# might work just a tad better. 28 inches behind the point will give you a one-inch overhang, which is sufficient to keep from drawing a broadhead onto your bow hand finger. The shorter (than 29-inch BOP) arrow will also be easier to maneuver while hunting. Will need to play around with your brace height and nock point to get good arrow flight. As a starting point, you might set your brace at 6 3/4 inches and nock point about 5/8 inches above the shelf, nocking the arrow under the nock point, of course. If your arrow fishtails, adjust the brace height higher. If it porpoises, adjust the nock point. If the arrow isn't bouncing off the shelf at release, raise the nock point. If it's clearing the bow cleanly but porpoising, lower the nock point. Of course, your arrow flight problems could also be caused by poor form/release problems. Good luck.

cbCrow · « **Reply #3 on:** February 22, 2011, 08:05:00 AM »

I would reccomend a test kit from one the suppliers on here. A lot will depend on where you shelf is cut to, 1/8 before center or to center, remember to include your arrow plate width. To find out if you are cut to center is to measure the distance across riser just below shelf than measure the portion of riser where plate goes.This should give some indication of center. If the bow is (with plate) 1/8 before center start your test kit at 55-59 than 60-64,65-69. and see what shoots best. The test kits take a lot of agrievation and expense out of getting the proper shaft.

tbird-51 · « **Reply #4 on:** February 22, 2011, 08:19:00 AM »

My experience has been that shooting points lighter than 175 gr, I need a lighter spine and a little longer shaft length, for your set up I would try 55-59 spine cut to maybe 30 in. and bareshaft tune from there.