CKruse - After looking at the points they appeared to me to just be some 1950s looking field points that were heavily knurled (sp). Looks like one just broke off at the knurling line.
Then I read down and see that you already came to the same conclusion. Great minds...
The knurling machine is a pretty cool little gadget that was used many years ago to secure target and field points to the shaft, but they aren't used much anymore. The machines I have had, can be adjusted to the depth of the knurling. Someone probably just set the machine a little too deep, then the bowman hit something hard and broke the point.
With the knurling in different places on the points, it might indicate our craftsman was a neophyte knurler (say that ten times real fast without stumbling).