Is 3 Rivers spine calculator accurate

[Ray Johnson]

I'm shooting a Centaur Chimera that is 44#@28".I draw about 27".I am shooting a Beman Hunter .500 that is about 30.25" long with a 100gr brass insert and 175 gr fp.The bare shaft hits right with fletched arrows at 20 yards.The calculator shows that my arrow is way weak for the bow.Now,the only option for bow type was the Centaur carbon elite which is faster than the Chimera but that was my only choice.I am not changing anything based on the calculator alone but I was just wondering what y'all thought.Have any of you found the calculator to be off on your setup?Also,do y'all think the arrow I'm using should be right for my bow?

[bulldog18]

I have found the calculator to be very close to right on for me. Not familiar with what type of bow it is as far as longbow, recurve, reflex/deflex longbow. If your exact bow is not listed you need to pick the generic setting at the top that fits your bow description and work the calculator from there.

[Ray Johnson]

I apologize for the numerous posts on same subject.I used my phone to post it and you see what happened.lol.Maybe a moderator could delete the extra posts.

[AZ_Longbow]

if you know a lot of exact bow information such as your center shot numbers as well as strike plates ,its pretty close... but you need to be as precise as you can.
you may be hitting your strike plate. if the bow is cut past center that could cause problems to for lower spine arrows.
try some different tip weights an try to verify your center shot numbers.
like all programs it is only as good as the input you give it.

[VA Elite]

I found it to be pretty close. Again like was said, the more particular you know the bow the better. also, try this site too. arrowperfect.com

[dbd870]

It is pretty close for me.

[Mr. fingers]

It gets me very close.

The reason I like Stu Millers calculator is it has a personal form factor which lets you make a known good arrow show correctly in the calculator. Once the PFF is set then most ever time I am real close with any new entries I make.

Don't know if 3R calculator has the PFF or not?

Bisch