I think I did a calculus problem years ago, as x approaches zero (deflection) y (bow weight) approaches infinity or some thing like that. man that was many moons ago.

Arrow Dynamics has a arrow Hammerhead that will spine about #100, Raptor Archery is testing them.

Hmmm. .5" steel thin wall tubing?    

I'm sure any sponsor you choose to utilize will do a fine job of getting you your required shafts at a safe spine for your use.

Got pictures of the beast being shot?

Yes its tough finding high poundage shafts. Be side howard hill archery its even harder to find a boyer to build a longbow or a recurve 100# to 160#. I know. once you reach 140# and abouve 2440 work great with a alluminum nocks or go to 7/16 diameter hard wood tapered 11/32 to and barrelled to 23/64 point. I have quite a few bows from 100# to 170# Marlon

Thanks for all the help, shafts are on order from Surewood.