I’ve had 3 M&P’s. A full size 40, Compact 9, and a 9 Pro and all of them have had a unique combination of these milled out “dots” on the inside of the slide.
Pro
Compact
I was at a gun store today and two Compact 9’s both had the same milled dots, but in different locations than mine and different from each other. I asked the guy at the counter (I know :rolleyes:) and he said it’s probably where the CNC made its contact with the slide during production. I don’t know if that makes sense though, seeing as how they would use the same program thousands of times to replicate all the slides (of the same caliber and barrel length) exactly. Plus, why would S&W take the time to unnecessarily mill something into their slides that would seemingly serve no aesthetic or useful purpose? Add to that the fact that the dots were different on two guns delivered to the same gun store from the same distributor at the same time.
I thought maybe they were there to balance the weight of the gun, but that doesn’t make sense to me because 1. the amount of metal being removed can’t be more than a few grams and 2. It’s different from gun to gun.
My highly uneducated guess would possibly be a date stamp? I know it doesn’t make since but it seems plausible to me. Due to 2 guns having the same markings and the rest different.
it appears there are two lines which the dots follow. With more samples id like to know which side carries more dots.
possible a CNC machine marker too. If they use more than one CNC machine to make slides.
Batch marks? some type of a mark to identify where that gun was made.
To me it makes since to have a way to tell were a gun was made, and to have identity marks. these are probably them.
Seems logical to me. however I’m probably wrong.
…and thus a new pursuit was born for M&P enthusiasts. “Which C&C did your gun come from? Mine’s from the best one - #4. Avoid guns from #6 and #10 - they will explode in your hand and give you a disease!”
