I broke my trigger return spring on my M&P today so I decided to do a full cleaning and parts replacement. I replaced slide release, trigger spring, recoil spring and striker assembly (I was still using the old black style striker).
After reassembly, my reset is laggy. I could hear it reset but the striker doesn't always fall when I pulled the trigger. I replaced the new striker assembly with the old one and everything now works 100%. Any ideas why the new striker assembly would be binding?
The replacement was the full assembly and not just the bare striker.
ETA: Turns out my striker was tuned with a trigger job I had. I will need a new trigger bar and sear to use a new striker.