Need your help please.

I'm trying to find the right arrow for my new 59 Kodiak (modern version).

THe 59K is 60" and 37# @ 28". My draw is 30.5".  I am estimating my draw at 30.5" is about 43#-44#.

I've tried the following Easton Axis arrows -

Axis 400 Black (fletched) - 30.5" - This arrow groups the best of all with 145gr points.  Nice flight, no kick.

Axis 500 Traditionals (fletched) - 31" - Shoots ok with 125gr and 145gr points.  Visibly kicks in flight. More inconsistent and bigger groups.

Axis 600 Traditionals - 30.5".  Tried bareshaft as 3Rivers spine calculator shows this should be a good match.  Shoots way right with 145gr and 125gr  points compared to the 500s and 600s.

What am I missing?  Why does the 400 spine arrow appear work the best and have the nicest smoothest flight?  Admittedly I have not tried this bare shaft.

Also the 3Rivers spine calculator does not list the 59K as a choice.  Which comparable bow should I try?

Thanks for any help.

I assume you're a right handed shooter.  Arrows impacting right would indicate a weak spine. Given your draw length, I would think the .600s would be on the weak side, though perhaps workable with a light point.  However, I'd also think the .400s should be too stiff.  The .500s should work. Might want to play around with more (higher) point weights with the .500s and certainly more for the .400s.

I shoot about 250-300 grains up front with Axis .500 and .400 shafts out of 45-50# bows, though I have a shorter 28-inch draw length and use a 29-inch BOP arrow.

Be sure to check your brace height and nock point to make sure they don't/haven't moved during your tuning. A too low brace height can cause the arrow to bounce off the side plate and fishtail in flight.  A nock point too low can cause the arrow to bounce off the rest and porpoise in flight. A nock point that's too high will also cause it to porpoise.  Sometimes a certain spine and fletching will mask these effects while another won't. That's what may be happening between the .400s and .500s.  The .500s should work the best for your set up in my opinion. 

One more thing to check.  Axis shafts are skinny.  Should work OK if your bow is cut to center, but will need to build out the side plate if it's cut past center.  My recollection is that '59 are cut to, not past, center.  Regardless, when the arrow is on the string, when viewed from the rear, the right side of point should line up just touching the left side of the string (or thereabouts).

Good luck.

Thank you Orion.  I appreciate the input.

I did put a toothpick under the side plate.  I'll try taking it out.

Thank you again Orion.

I removed the toothpick under the side plate and it really cleaned up the flight.
Narrowed it down to the Axis 500. Just trying to decide on the 125 or 145 gr tip and Tweak the brace height.

That bow has a DynaFlight 97 string (factory) which is probably why the 600's were too weak. 

Axis 300 work for me out of both 50 and 60 lb longbows. Go to town on the tip weight on the axis 400.
Most carbon shafts are way too stiff , even at full length.

Glad it's working for you. Most bows will shoot a range of (dynamic) spines.  It will probably shoot both the 125s and 145s just fine. 

OP, I also have ~30.5" draw and shoot 40-45-lb bows. I'm using full length gold tip traditionals, 400 spine. For the heavier recurve I use 145gr points and for the longbow, 175gr points. 500s might be ok if I cut them, but even with 100gr points they are weak.