shafting and spine question

[Fishnhunt]

Hello everybody.  New guy here (new to the site and new to trad archery) and I have a few questions regarding the proper carbon shafting for my bow.  My bow is 40# at 28” and my draw length is approx 26”.  Last year I shot 29” 2016 arrows w/ a total finished weight of 525 grains.  I was relatively accurate w/ those arrows but penetration was lacking ( I think the penetration problem was due to poor arrow flight).  This year I’d like to use carbon instead of aluminum and I’d like to keep the finished weight around 525 grains.  I’d also like to front load as much of that weight as possible.  
It looks like I could achieve my desired weight by using the following:  165 grain broadhead + 100 grain brass insert + 260 grains of shaft (Axis ST 500 @ 8.1 GPI cut to 29” plus nock, feathers, wrap).  
Would such an arrow spine correctly?  Am I correct in thinking that a 500 carbon cut to around 29” with 260 plus grains up front will spine correctly from this bow?
Is there any place to buy single arrows instead of a half dozen?
 
Thank you!

[Dean Lintz]

I have found bare shaft tuning works best for me. Put the weight you want up front start with full length shaft shoot it if right handed should be knock left or week. I trim 1/4" at time until it is flying straight. Then put your feathers on and should have no problems. As long as arrow does not end up to short I would rather have an arrow fly straight at 30" than fishtale at 29"

[Mo. Huntin]

I am so lucky to have some of these small bow shops around.  I can buy just one arrow if I want.  I shoot a 45# Montana at 27 inches with a full length 1916 with a 175 grain head.  I bet you would need atleast a 600 spine for your bow.  I have some 500 spine gold tips full length that I put a 100 grain brass insert in and a 175 grain broadhead on they fly good but I think they are even a little stiff for my setup.  Just my experience.  when you find a arrow you think will work do a search for it on here and read the results, lots to learn from these fine folks.

[Mo. Huntin]