I am looking on the spine chart from 3 rivers archery. I am shooting an Omega Original. 43@27.5 and I draw 27.5. If I change my arrow length 1" it changes my spine from 500-400. If I change tip weights any it changes from one to another. If Im right on the edge should I go 500 or 400. I am looking at purchasing the Beman ICS Bowhunter.
Unless you're putting more than 300 grains up front, the .500s will be great plenty. Shortened to 29 inches BOP, the .500s should be fine with a fair amount of weight up front as well. .400s will likely be too stiff regardless of what you do to them. A .500 is about a 63# static spine; .400s are about 78# static spine usingEaston's way of measuring spine. In fact, if you don't put a lot of weight up front, you might even be able to shoot .600s.
The spine charts only get you in the ball park. From there you go on trial and error and/or experience. My recommendation is based on my experience.
I agree with Jerry, I would go with the .500's at 43# if .600's aren't an option.
Also, carbon arrows seem to respond to shaft length much more quickly than point weight in my opinion.
I considered 600's but they get really light. I did find the Easton Tributes which are available in a1916 and are 10 gpi. Really considering them to have the extra weight.
I guess it depends on what one considers light. On low 40s bows, my .600 arrows finish out between 9 and 10 grains per pound.... Plenty for me and the lighter shaft makes achieving a decent FOC really easy.
It is situations like this that a test kit really can make the difference. Not to push you into spending more money, but it could make the difference. That said, I would feel good about doing the 500 spine, long as you are cutting them in the 29" range, standard-ish point weight, and don't creep when you hit anchor.
Like said above, unless you are putting a LOT of weight on the front end, I don't see any way you can make a .400 spine shaft work from a 43# bow. With my 44# at my DL bow, I shoot a .500 with a standard insert and a 145gr point. Only first hand tuning will yell you for sure though.
Bisch
You got some good advice from these guys.
Especially if you creep or don't get to your full extension or a different angle (tree stand shot for instance) it would be best to have an arrow that flies well when shot with a slightly shorter drawlength.
Speaking from experience on this one. I made a poor shot last fall because of the above, I recovered the buck but was not pleased with the arrow placement.
500 - 400 will be super heavy at 43 lbs of draw
Yep. What Orion said. 500 spine will be plenty.
You got some good advice from these guys.
Especially if you creep or don't get to your full extension or a different angle (tree stand shot for instance) it would be best to have an arrow that flies well when shot with a slightly shorter drawlength.
Speaking from experience on this one. I made a poor shot last fall because of the above, I recovered the buck but was not pleased with the arrow placement.
Thank you to everyone. Greatly appreciated.
.500's sound really stiff for a 27.5" draw out of a 43# longbow. I'd look into a set of .600's and adjust the point weight and arrow length from there.
In my experience a slightly stiffer arrow will fly better than a weaker arrow BUT .500's will most likely be too stiff unless you plan on putting 300 grains up front and leaving the arrow long.
The bottomline in my opinion is that .600 spine is a much safer option.
I wouldn't even consider 400s...way, way too stiff. Depending on the center shot of your bow, you will likely be able to get 500s to shoot well, but they will be approaching 11 grains per pound of draw.
Here is what works for me with my Kiowa, bearing in mind I draw 27", so I may be a pound or so less draw than you. I'm shooting Easton Powerflight 500s (same as the ICS Bowhunter) cut to 29" with 225 grains up front. This gives me the option of using a 100 grain insert with my 125 grain Bullhead for turkeys or my 125 grain Stingers for deer or a 50 grain insert with Zwickey Deltas or Simmons Tigersharks at 175 grains. They fly like darts, even with bare shafts. This combination with 3 4" feathers weighs 465 grains. With Vanetec .288" vanes they are 472, both with a 1.5" wrap of reflective tape around the shaft...keeps me from losing so many arrows, lol.
This works for me. I would say, it may get you close. I also agree that carbons are VERY finicky about length, but fairly forgiving of point weight. This combination shoots pretty flat out to 20-25 yards, which is WAY farther than I plan to shoot at game anyway. I think I am around 21% FOC with this setup, if that makes any difference to you. I like it because of my relatively light draw weight. I want all the penetration I can get.
Hope this helps. Oh, and .600s will work and shoot a bit flatter, but as you noted, you will give up some weight.