I have both the full size and compact 40's. The full size is an issued duty weapon and I loved it when we were issued them. Although I noted during our first range firing, that the range officer cautioned us as to allowing our grip to overlay the magazine release.

He said that it could cause the weapon to drop the mag and that we would not be given alibi's if that happened. I did not have any problems either firing or qualifying with the M&P 40 and loved the weapon by the end of the day.

The problems came when I attempted to carry the weapon off duty in my waist band. I have carried both revolvers and autos in my waist band for years off duty. I carry an auto on my right hip, just to the right of my back pants pocket, with the clip facing to the side as opposed to facing the small of my back.

This has always been the most comfortable carry for me, for both auto pistols and revolvers..

As I carried the M&P 40 in this fashion, I soon discovered that the magazines was continually disengaging and popping the clip out of the pistol. Which is not a good thing if you might need your weapon quickly. I got use to reaching back and frequently checking the clip and often having to re-seat it into the pistol.

About three weeks ago, I bought the M&P 40c compact and once again, I love how the pistol feels and shoots. But when I carry it in my waist band? The exact same problem arises. The clip releases based upon nothing more than the pressure of my waist band. And now I have discovered another problem with the compact. I purchased a nylon ankle holster for the compact? And I have the same problem with the clip disengaging while seated in the ankle holster. Apparently the pistol riding next to my ankle with the mag release up against my leg is what causes it.

So, after examining both pistols and trying a number of trial and error things to activate the magazine releases, I have determined that there is obviously a problem with these magazine releases on both models. Simply put, the retention springs on the mag releases are too weak and this causes the release to be super sensitive to pressure and release the mag. Almost any pressure on the magazine release and the magazine releases every time.

So I contacted S&W directly and explained the problem. The tech was sympathetic, but said that as both of my pistols were relatively new, and that as such all existing previous magazine issues had been addressed by Smith and corrected. However, he said that he would send me two new magazine releases to swap out on my pistols.

Once I receive them, I intend to take the pistols to a gun smith and have him examine the current releases and then install the new ones. I will see how this works out. However, I am of the opinion that the fault here rests with a weak spring in the magazine release assembly. I hope they send new springs also.And I hope this resolves the problem.