I need to know what the proper size and spine should be for a 175# draw weight crossbow.     What will too light shafts do?  What will too heave shafts do?  New at the crossbow game and the 16" 2219's will not zero.  Seems like there is no rhyme or reason to the way they fly.  Sometimes way off target, more than two feet at ten yards, and that isn't really that far away.

what bow are ya shooting? Also what type of nock on the arrows ya shooting. Archery is pretty simple once ya get the basic set up done correctly. Each bow will have different requirements to perform at its best. You also need to cock the bow the same each and every time. Its best to use a rope cocking aid. If ya cock the bow by hand you could be pulling the string left or right differently.

archery needs consistency to be accurate.