What does the safety on the M&Ps actually do?

Does the M&P manual safety lock up the trigger or what does it exactly do?

Also, does the safety have to be off (down) to be able to retract the slide, like a 1911 or can a round be chambered with the safety up?

I haven't tried one in a gunshop yet; do these safeties work hard and have a positive click when engaged?

shooter7 said:

Does the M&P manual safety lock up the trigger or what does it exactly do?

Also, does the safety have to be off (down) to be able to retract the slide, like a 1911 or can a round be chambered with the safety up?

I haven't tried one in a gunshop yet; do these safeties work hard and have a positive click when engaged?

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Good questions. I hadled one briefly. I do remember that the safety worked easily and there was a positive click. I don't think the slide can be racked with the safety engaged. But I'm not positive.

Im no expert on these, I think the safety replaces the lock with a lever that blocks the trigger. I have a M&P 45 with the saftey and yes you can work the slide with the safety engaged. I like this as you can load and unload with the saftey on. It does engage with a click but is not as positive a feel as the safety as a 1911 style gun. All in all I like the safty as it adds a level of security if someone gets your gun from you, it's one more thing to figure out to make it go boom!

Blocking the trigger would be a complex mechanical process involving long levers that would have to get past the magazine well. While I don't know, I expect that the manual safety operates like the magazine safety/disconnector and moves the trigger bar so that it won't release the sear. Or, it might block the sear. Both of those are possible with rather minor changes to the sear block.

Vulcan Bob, how's about a quick trial and let us know? Operating the safety with the slide assembly off should let you determine what's going on.

I had emailed S&W 2 or 3 times and asked them to explain how all the safety features work on their M&P models in detailed layman terms.

I was trying to decide if I wanted to sell my 40 compact and buy one with a thumb safety. Not really comfortable carrying with one in the chamber till I know what feature and how it works will prevent the firing pin from accidentally or by malfunction striking the bullet.

All I ever got was 1 response that asked what model and serial number I had. Nobody else from there ever replied. I was shocked because they are so well known for their service.

Never had one apart but I would guess that it blocks the sear from releasing the striker. It still incorporates the firing pin safety where the trigger bar lifts the firing pin block that keeps the striker from going forward till the trigger is all the way to the rear.

handgunner356 said:

Never had one apart but I would guess that it blocks the sear from releasing the striker. It still incorporates the firing pin safety where the trigger bar lifts the firing pin block that keeps the striker from going forward till the trigger is all the way to the rear.

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So there is an actual physical block that blocks the firing pin till the trigger is pulled? And if the sear should malfunction / break and the pin comes forward this block would keep the gun from firing?

That is the theroy. On third generation guns there is a lever that lifts the firing pin block, on the M&P it's made as part of the trigger bar.

I guess my reason for asking was, that I was looking to get an M&P, and I thought that if I used it at the range in a holster extensively, the lever safety would be one more safety against some sort of accidental/negligent discharge, when reholstering.

I've met two people who in the past have shot themselves in the leg, when reholstering; one with a 1911 where they forgot to put the safety on a when it was cocked and a round chambered and when they reholstered, they didn't keep their finger out of the trigger guard. His fault obviously.

The other incident, was with a dao gun, no safety, and when they reholstered, a shirt tail or some piece of clothing, got caught on the trigger, and bang. The guy showed me the scar down his leg, to make me see what could happen if you're not careful. In this instance, if a manual safety had been on the gun, and the safety engaged, the shot would have never went off.

I saw a rookie cop shoot himself like that with a Glock 22. Left an impressive scar as well.

He was wearing a raid jacket with drawstrings on each side. One of the plastic pulls for the drawstring flopped over into his holster. He reholstered and it went inside the trigger guard and......

Another reason I don't like DAO striker fired pistols with no safeties. Regards 18DAI.

handgunner356 said:

That is the theroy. On third generation guns there is a lever that lifts the firing pin block, on the M&P it's made as part of the trigger bar.

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Wow, I would hate to leave it up to theory. Can anyone confirm this for a fact?

18DAI said:

I saw a rookie cop shoot himself like that with a Glock 22. Left an impressive scar as well.

He was wearing a raid jacket with drawstrings on each side. One of the plastic pulls for the drawstring flopped over into his holster. He reholstered and it went inside the trigger guard and......

Another reason I don't like DAO striker fired pistols with no safeties. Regards 18DAI.

Click to expand...

Oh yeah. It can be a scary thing to see someone stuff their striker-fired pistol into a belt holster and be unaware they've captured some article of clothing with the gun in the holster, especially something which is forced near the trigger. Much like watching someone reholster a cocked 1911 without engaging the safety lock (thumb safety) or a revolver with the hammer cocked in single action. Scary.

The thumb safety on the M&P series incorporates a metal surface on the right lever which, when raised, blocks rearward movement of the trigger bar and prevents it from reaching the sear nose (and lifting it up to release the striker). The lever can remain raised (on safe) while the slide moves.

The magazine safety operates differently, from the opposite side of the trigger bar, so to speak (on the 'inside' of the trigger bar's tail). There's an angled surface on the steel safety lever which deflects the rear of the trigger bar away from the sear (to the right) when the lever isn't being lifted upward by a magazine. Its' really a pretty simple design compared to that in the 3rd gen guns.

The M&P striker safety plunger is lifted by a vertical extension of the trigger bar, much like the Glock and 99 series, which lifts the plunger when the trigger is being pulled.

In the 3rd gen S&W pistols there's a dedicated firing pin safety plunger lever which is moved by pulling the trigger (moving the lever to lift the plunger and free the firing pin for movement). Pulling the trigger pushes the drawbar forward, and the bottom of the pivoting FP safety lever is pushed forward by contact with the drawbar, lifting the top of the lever upward against the safety plunger.

Thanks Fastbolt, I was about to go and get the M&P .45 and check the operation of the saftey. It felt like a trigger block but after W R Moore's post I was going to look and report back.

Please excuse my less than professional pictures, but I have an older camera which doesn't do close ups well, and I'm not taking my time to position things as well as some other folks do when taking pictures. I'm just trying to hold the frame steady with one hand, manipulating the trigger bar (and holding a brass punch) and taking the picture through a magnifying bench lamp with the other. Not the steadiest of positions ...

Anyway, here's a couple images that may help a little.

Here's with the safety lever in the UP, or on, position. Notice the curved metal part pushed up against the rear of the trigger bar where it makes a 90-degree turn inward (the trigger is being pressed until it's stopped for illustration only). Notice how the angled ramp of the rear of the trigger bar has not reached the front of the sear. (I edited the image to make it a bit brighter and reposted it.)


Here's an image where the safety lever is in the DOWN, or off position, allowing the trigger bar to move rearward enough to have levered the nose of the sear upward. The tip of the brass punch is pointing to the front of the lever's angled arm which was previously pushed up against the rear of the trigger bar in the last image. (I bumped the trigger bar outward - to the right- with the brass tool and disconnected the rear of the trigger bar from the sear, however.)

Davidwilp-the M&P has a two part striker safety system. There's the firing pin plunger, which locks the firing pin until the trigger moves the trigger bar through its entire travel. There's also the hinged trigger that prevents the trigger bar from moving unless there's a finger-or other object-that moves the trigger through its entire travel.

In other words, it isn't going to go boom unless the trigger is stroked its entire travel. FWIW, the trigger on a stock M&P is similar to that of a very well tuned revolver. Do you have to be careful about holster selection, digit placement and making sure the holster is clear before inserting the weapon? Yes, but you should be doing this with any weapon system. Do not EVER depend upon mechanical widgets to protect yourself from injury.

WR Moore & Fastbolt. Thank you. I feel a little more comfortable now. I have carried a snub nose for years and never ever gave it a second thought. Never bothered me in the least. Just put it in the holster, put it in my pants (appendix) and off I went.

Since I bought the M&P 40 compact about a month ago I don't carry it pointed at my privates and have yet to carry with 1 in the chamber. I know I need to but it is this mental thing about something not working as it should and boom.

There's something to be said for those long & heavy DA revolver triggers.

I'd never recommend that someone carry a handgun as a defensive weapon if they were uncomfortable with it. Never. Just like I wouldn't suggest they get a driver's license and a car if they weren't comfortable with the idea of driving and felt they'd rather get around by other means. Or learn to ride a motorcycle just because they were comfortable driving cars & light trucks.

I'd never consider recommending someone carry a semiauto if they were more comfortable with DA/DAO revolvers (presuming they had a choice and it wasn't a job requirement, of course).

I try to shy away from making specific recommendations to folks unless I know something about their knowledge, skills and experience ... and I'd really prefer to have had some time working alongside them on the range.

I've never disagreed with a non-LE shooter during a class when they said they weren't comfortable carrying a semiauto pistol and only wanted to carry a DA revolver. Their choice. I agreed with them understanding the limits of their knowledge (familiarization & safety), training, experience, confidence and comfort and choosing to use a revolver if that's what they used safely and well.

I've seen some folks shoot their revolvers noticeably better than their 'new' semiauto pistols, too.

In forums like this one I'll sometimes explain some of what I've learned about some firearms as an armorer, but it's only for the purpose of polite discussion and general informational purposes. Not to recommend or convince someone to do something with which they're unfamiliar, or lack the training and experience to know how to do it safely. That's for the folks who can be present as 'hands-on' trainers, not something done over the internet.

I don't care how many safety features a firearm may possess, either, I don't like to completely place my trust in them to the exclusion of experience and common sense. I like to minimize my exposure to unnecessary risk. The longer I'm around firearms, carrying them and training in the use of them, and helping train others to use them, the more cautious and conservative I become in my approach to handling, manipulating, carrying them and using them.

BTW, I carry a S&W J-frame more often than I do a semiauto pistol now that I'm retired. I use a pocket holster, though, to keep the trigger guard covered. Just in case.

It pays to be safe. There's a saying in risk management circles ... Predictable is Preventable.

I love my new 40C and I want to carry it. I just need to get comfortable.

Thanks for the internal gun pictures!

You're welcome. There are better ones floating around the forum somewhere, done by folks with much better cameras and more skill, though.