Primitive Archer

Main Discussion Area => Arrows => Topic started by: sleek on July 20, 2020, 11:16:30 am

Title: Cutting arrows and affects on spine
Post by: sleek on July 20, 2020, 11:16:30 am
So I need some arrows spined for a 26 inches, and of course arrows come longer than that. So, if they are 32 inches spined for 30, and I cut them down to 27, will the spine go up to a 40# spine?  When arrows are spined, are they spined with a specific weight arrow head in mind? How do you know what weight point to put on?
Title: Re: Cutting arrows and affects on spine
Post by: jeffp51 on July 20, 2020, 12:51:59 pm
arrows are spined based on a 28" length from the base of the knock to the base of the point.  As a rule of thumb, if you cut off one inch, the actual (dynamic) spine will go up by 5#,  so an arrow marked 50# for 28" will actually shoot like a 55# spined arrow if it is 27" long.  For a 26"arrow, you could use -10# as a starting point. If you are shooting a 50# bow, you might start with 40# spined arrows.  However, there are so many variables (point weight, degree of offset of rest,  fletching, etc) that you just have to test them a lot.  If you are like me, the real problem is just shot consistency that have a greater effect than spine. 
Title: Re: Cutting arrows and affects on spine
Post by: DC on July 20, 2020, 01:00:15 pm
125 Grains is the default