Hard to say about crowns since absent of obvious damage, one can never really be too sure.

I just fired 3 targets with my M&P9L this Wednesday evening. 25 yards, rested, 115 gr Federal AE. Five rounds each.
3-3/4", 3-1/2", 6-1/2".
No shots were "called" on the last target.

I have had similar experiences with this gun as long as I have owned it. I'm not entirely confident of the quality of the ammunition, so I will try again next week with something else, or a couple of somethings else. If I recall correctly, this gun always shot best with Hornady 124 gr FMJ-FN bullets, but even with those, it is erratic.

I agree a new barrel would seem to be indicated, but I think I will try to re-crown the factory barrel since there is nothing to lose. The gun should shoot into 2-1/2" to 3" with good ammunition, to be of any value to me.