Wendall
This might be of interest to you and others shooting the M&P. Todd Green is a wel respected firearms instructor and has done testing for S&W. Here are his comments regarding the mag disconnect. All might note that the M&P trigger pull is not affected by the mag disconnect.
"Gun grabs -- Smith has a mountain of testimonials from police officers whose lives were saved because, while wrestling over their sidearm, they were able to eject the magazine and disable the pistol. When the BG got the gun, he had nothing but a paperweight. Reality has taught us that sometimes proper weapons retention training and techniques won't be enough. While a BG might be able to figure out how to disengage a safety, odds are he isn't walking around with a spare M&P magazine.
Administrative safety -- One benefit of a SFA pistol is that it's easy to shoot. One disadvantage is that it's easy to shoot accidentally compared to guns with longer and/or heavier trigger pulls. While a lot of gun owners and instructors like to act holier-than-thou and proclaim that they could never make a mistake, I don't consider myself infallible. The ability to deactivate the firing mechanism during administrative handling might sometimes come in handy.
Proper disassembly procedure -- I've seen too many ADs caused by people pulling the trigger to disassemble an "unloaded" gun. Well, with the mag disconnect mechanism, this is all but impossible in an M&P.
There are also some arguments against it:Take
On some guns, a mag disconnect safety can impair the trigger pull. This isn't the case with the M&P.
The oft-cited "ability to shoot in the middle of a reload." Sorry, I've been unable after more than a decade of searching to find a single instance where anyone has had to do this in a fight.
First, most reloads during a fight occur at slidelock ... so there is no shooting possible until you put a fresh mag in the gun.
Second, if you are performing some other reload (by definition, a discretionary reload instead of an immediate action reload) then you should have enough situational awareness that you aren't going to be threatened during that split second it takes to eject a mag and insert a new one.
Third, if you did get surprised in the middle of that moment, your brain isn't going to stop and reverse course ... finish the reload and then finish the fight; firing one shot and then having a gun that needs a new mag and a rack to the slide is going to eat up a lot more time.
It makes dry-firing a pain in the butt. This affects both dry practice as well as the mandatory "unload & show clear" procedure used at IDPA and IPSC matches.
That's a longer explanation than is probably necessary. Basically, I see the advantages (primarily the defense against a gun grab) as outweighing the negatives (particularly the fanciful notion of a mid-reload desperation shot). If I can make the gun a little safer without any loss to practical ability, why not use a mag disconnect? "
Take Care
Bob