My last post I asked for the formula to calculate spine ( and thank you ) I have done the math,now I ask to be double checked, here is what i have.
B/W saii
60in
58#@30in
3/16in past center
f.f.string
31in bop arrow (full length)
145gr point
80# spine???
Stalker 3pc lb
64in
i/8 past center
ff string
55# @30in
145gr point
74# spine????
I'm going to order a test pac from Surewood,of 70-75,75-80,80-85,85-90 I would like 10gpp, Does this sound right??? thanks Burt
I think your test pack is in the right area.
Yep that test pack will probably have arrows for both of those bows.
I came up with 93# for the BW and 80 for the Stalker.
BW: 15 for 3/16 past, 5 for FF, 5 for 145, and 15 more for 31". Personally I think you will be pushing 100 depending on your shooting style, and if your draw is correct.
5#s for every inch over 28"s, that gets you to 75#s another 5#s for the 145 grain point, than another 10#s for high performance recurve cut 3/16ths. past center. That gets me to 90#s for the Widow, so maybe a bit stiff. I would say 85-90#s for the Widow. Arrows by Kelly had a great spine chart for woodies and that is what I always swore by. Shawn
I agree with Bjorn but I always tune a tad weak and added 10#s where he added 15#s as once you fletch them up and add a broadhead they stiffen up just a tad. Shawn
At the spine these guys are talking about, and I tend to agree with them, it's going to be difficult to come in at 10 gpp with Douglas Fir. Might be able to do it with Sitka spruce or POC. Difficult to find the length and spine shaft you're going to need that is also physically light enough to to make a 10 gpp arrow with a 145 grain point. You're much more likely to end up in the 12 gpp range, still very good, IMO. That's mostly what I shoot.
here is my math.
bw is 52# @ 28 +10 for 30in=62
3/16 past center+15
ff string(I forgot)+5
145 point +3
=85#
I'm glad I asked you guys,I forgot the string,Thanks Burt
With a field point arrow you don't "have" to leave the shafts full length. A 145g point is about 1" long before the actual point. By cutting them 29" B.O.P, or so, the Point will make it a 30" arrow. Pull right on into the rest at your full draw. You will lessen your need for such stiff shafts. Sound dumb?? Howard Hill did it all the time.