He may be in one of those areas where hollow points are not allowed...
If so, see if the Federal Guard Dog expanding FMJ are allowed.
As was said... every time you load and unload the same round over and over, setback can happen.
Setback that extreme suggests to me a poor round crimp due to cheaper FMJ... or even a squib round that has no powder in the case and allowed to to be pushed back that far.
If it was a squib... it is most definitely a good thing you found it as you did.