Surewood Shafts Mass Weight

Mass Weight

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A common question is; “What should I expect for mass weight from Douglas fir?”

Without getting into the details of how much you are going to cut off due to your draw length or what you are going to add back on as finish, point weight, nock, fletching etc. I will leave that math up to you. The table below should aid you with a starting point for your raw shaft from which to start.

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Please Note

Spine weight Grain Weight
30-35 lb 330-380 gr
35-40 lb 340-380 gr
40-45 lb 350-400 gr
45-50 lb 360-410 gr
50-55 lb 370-420 gr
55-60 lb 380-430 gr
60-65 lb 400-450 gr
Spine weight Grain Weight
65-70 lb 410-460 gr
70-75 lb 430-480 gr
75-80 lb 440-490 gr
80-85 lb 470-520 gr
85-90 lb 480-530 gr
90-95 lb 500-540 gr
95-100 lb 510-550 gr

Spine: “The stiffness of the shaft is known as its spine, referring to how little the shaft bends when compressed. Hence, an arrow which bends less is said to have more spine. In order to strike consistently, a group of arrows must be similarly-spined. Higher draw-weight bows will generally require stiffer arrows, with more spine (less flexibility) to give the correct amount of flex when shot.”    Wikipedia

Grain: “ A unit of weight in U.S. Customary System. Traditionally arrows and shafts have been weighed in grains, 437.5 grains equals one ounce. ”

If you want more technical information please go to Stu Miller's Dynamic Spine Calculator.