One of the more interesting aspects of the single stack M&P Shield, is that it isn’t a single stack… but it isn’t quite a double stack either. It is about a 1.4 stack?
The M&P magazine slightly staggers the rounds to increase the capacity, without increasing the width of the pistol. Looking at the M&P Shield next to the Kahr PM9 you can see that they are essentially the same size (.01″ difference in frame width). I find this to be a significant accomplishment with a magazine that it .17″ wider through the body.
Compared to the full size M&P9, the shield has very tight tolerances between the magazine and the sides of the mag well, with roughly half the tolerances. However, when compared to the PM9, the mag well is simply cavernous. This difference is magnified by the 1.4 stack design and the magazines neck.
As an added benefits the slimmer profile of the magazine make it easier for me to conceal than my double stack Glock mags and easier to handle than the .479″ wide magazines of my Kahr.
There is one dimension that confuses me though…
You would think that with the semi-stacked design that the magazines would be significantly shorter overall for a given capacity than the single stack competition… it’s not?