it was only one but it did shove back into the case. figured a crimp would solve this.
Is this new brass? if not the one case may work hardened. If so, no amount of crimping will solve the problem. I don't normally crimp 223 but if I were loading the bullet in the pic, well it's just screaming to be crimped. What I would do like already said is to trim the brass to the same length. I would seat the bullets and then come back with a light crimp. Oh darn M&P, do ya hear a echo?