North61,

Contrary to popular belief, bullets do not become less stable further downrange. They actually become more stable, due to spinning just about as fast while air pressure on the front end of the bullet decreases due to less velocity.

Your problem with the 225 AccuBond and downrange accuracy is due to something other than the 1-16 twist.

“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck