Swaged nocks!

[moebow]

And you're playing serious Russian roullett(sp) if you don't glue them on!!!!!!!!!!!!!!!!!

[Killdeer]

" it was the "ear" of the nock that had split/busted. "

This is a typical break for an aged nock. I would suspect the nocks themselves. I go out of my way to buy shafts with swaged nock ends. I love my glue-ons.

Killdeer

[Smallwood]

like killdeer said, it sounds like the plastic nocks are bad/brittle. just buy new ones and see if that solves the problem.
you can glue them on with fletchtite, or whatever.

[GWert]

Did you ever see one of those cone shaped wood splitters? The nock end of the shaft looks the same as the wood splitter, right? If you don't glue the nock in place, when you let it fly you are trying to force the nock into the cone and if it is not glued on it is bound to break. just my opinion