It's a S&W M&P. Not a 1911.
Sear modified, so maybe a similar issue, but I have no way of knowing since I know nothing of the inner working of the M&P.
Ah well. Guessed wrong. Probably.
But now we know if you mess with the sear geometry of a 1911, bad things can happen, and if you mess with the sear geometry of a 1911, bad things can happen.
I know 1911s. I have spent thousands of dollars learning 1911 gunsmithing. From a very good gunsmith. and I barely can even SEE when a 1911 has a similar flaw. If you handed me an unloaded 1911 with this problem to test for this there is a slight chance I could catch it. (You take out the thumb safety and watch for the issue thought that kidney shaped window. The trick is doing the trigger pull right.) So be a gunsmith better than me to avoid something that happened to Ms. Eisenzimmer from happening to you.
Also, at the Army Marksmanship Unit, they have the best 1911 gunsmiths in the world working as their armorers and the guns are very well tuned. They tell some the best and most talent shooters in the world to never go into the gun and make alterations on their own. They can even ORDER them to never go in and make alterations, as the shooters are soldiers with a chain of command over them. Some AMU shooters still go in and make unauthorized alterations. Yikes.
Be careful out there.
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