S&W 645 Decocker/Safety question-

ScrapmasterFlex

ScrapmasterFlex

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Hi everyone-

I just got a S&W 645 .45ACP and I'm very happy with it. It's 30 years old and not a safe-queen but it's in pretty good condition for said age and 'shooter not safe-er' status.

My question is with the decocker-safety. I am wondering how 'safe' the decocking is. I have never owned a decocker-safety type pistol before, as I am much more into SIG's frame-style decocker. I read once that SIG's decocker was a much safer style of decocking the hammer (not necessarily because it was frame-mounted, that's not what I mean, but in the way its process operates) vs. for example Beretta or even HK's decocker button.

So I am wondering -- OTHER THAN the obvious rules of gun safety , not having the muzzle pointed anywhere dangerous nonwithstanding -- is there any risk or perhaps I should more accurately say, heightened risk or elevated-level of risk when decocking, of accidental detonation? I am pretty sure I've read how Glock and S&W for example, on their M&P, it's physically impossible for a round to be fired without squeezing the trigger due to the way the striker is set, tensioned, released, etc. I am just trying to make sure the S&W 645's decocker is something I have to be extra careful with or anything like that. I'm concerned I'm not wording this carefully enough, I'm not talking about being a moron or anything - it's just a new type of equipment for me and I'd appreciate any info from the brain-trust I can get. Thanks much.
 
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I was trained on the 645/4506, and other generation 3 S&W .45 pistols. Once the hammer is cocked, if you are done firing them, for safety you must decock it using the lever. It is very safe to decock the weapon. Most of my pistols are DA/SA which require use of the decocking lever. If you fail to decock the pistol, it is in single action mode, and a light trigger pull will fire the pistol. Therefore the risk is in NOT decocking it.
 
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This is a fine question and I can assure you that you look 180 degrees from a moron for asking! ;)

The decocker is difficult to "get on board with" sometimes because of what we can obviously see. That hammer FALLS. Frankly, it should scare the tar out of anyone handling a handgun -IF- they don't understand the nuances.

First thing it does is physically block the rear end of the firing pin. This is good for safety! And another thing you cannot see is that the firing pin itself is LOCKED in place from underneath and the only possible way to unlock that firing pin is to actuate the device that physically unlocks the firing pin-- it's a lever pushed by the trigger.

What this means is that using the decock lever on a 645 is actually, physically safer than the old-school method of carefully squeezing the trigger and safely lowering the hammer.

When the chamber is loaded... for piece of mind, you certainly can still safely (slowly) use your right thumb to lower the hammer -- but do NOT use the trigger to begin that process. Use the decock lever.

I hope I explained this simply--
If I didn't, ask more questions. Someone else may find a better way to explain it!
 
Both of you thank you very very much for your very helpful responses and certainly your politeness.

I am no novice , and have a better grasp of firearm mechanics than your average half-aced collector/shooter but I've definitely got limitations and while I'm capable of reading about technical things, understanding - for example- the differences in decocking mechanisms between firearm brands and stuff gets a little technical for me.

I am very happy I asked- I definitely didn't want to suggest I'd carry it chambered with the hammer cocked. Just wanted to make sure I wasn't at risk each and every time I'd have to decock it. My plans right now are to use this as my open-carry yard-gun ( got about 30 acres or so of property in the Scrubland and while I love 9mm and even .40 S&W for what they are, in the even a hog or coyote or even worse decides to try me, I'd feel a lot more comfortable with a good-old .45 Auto hardball helping me.)

So far I love this gun... It's well-used but looks a lot better than you'd think , and I'm conssssssiderrrrrring the $400-ish Robar NP3+ refinishing package . ... It's my understanding that when you get the top-end packages, they refinish each and every part, interal, etc. slide, frame, etc. So I'd have a brand-new used gun with lots of character/soul and certainly reliability and firepower. All agree the 645 is dead-nuts reliable, it seems to me.

Again thanks I am happy I asked, you two couldn't have been more helpful.
 
Haha, nice. I can't say I (myself) would go the Robar/NP3 route, and not because it isn't quality (oh it IS, bigtime, top notch)

...but because a 645 is as tough as they come. Robar/NP3 would notch up "cool factor" in a big way for sure. But tangible benefit, especially with regard to cost? I don't see it. But if you do go ahead with it, I can tell you this audience will LOVE it, haha.

Back to the subject -- it makes sense to point out here that 1st Gen S&W pistols do NOT have the firing pin lock that 2-3rd Gens have. Your 645 is a 2nd Gen.

There are some (older and seemingly isolated) reports (but some from credible source such as the ISP) that 1st Gen de-cocker failures HAVE happened. 39's, 39-2's and 59's. The block that rotates up and guards the rear of the firing pin shatters and the hammer energy -is- transferred to the UNLOCKED firing pin.

Saying this simply to say that quite frankly, the 2-3rd Gens are far more safely de-cocked than any 1st Gen. The 2-3rd Gens have redundant safety systems -- multiple layers where the slight possibility in the failure of one system is wholly backed by another system.

Of course, hardly needs to be said, muzzle direction awareness a full 100% of the time. That's human safety redundance, and nothing will ever top the Four Rules.
 
Also, just as an interesting side-bar (because you ventured in to a discussion area where folks are passionate about S&W metal pistols), there is a chance you may not realize that S&W did a short foray in to the Sig-style lower-frame mount thumb decock lever.

Other know the details of history better than I do -- I believe it was a direct request for the FBI contract 10mm chambered Model 1076 pistols. S&W made them on the 1076/1046 and on some 9mm and .40cal pistols also. I'm uncertain if they did any in .45cal?

They aren't all too popular it seems. Look for Models 5946 and 4046. From what I gather... almost nobody believes that S&W did a very good job at their version of the Sig-style decock. Many believe they look and feel "flimsy." But they do offer that familiar system where you can slowly lower the hammer through manipulation of the thumb lever.
 
Sevens I am familiar with the fact that S&W has made some frame-decocker decocker-only pistols , including in 9 and .40 (all them I'd be somewhat interested in.) - The thing is, someone said in a post I found on Google (and I am NOT saying this is true, I'm just saying I read this) that the the decocker-only frame-decocker S&W models don't have regular hammers? So you can't cock them, decock them, cock them again, etc. Almost like they're DAO or something along those lines. I have Googled the pictures too, they do in fact have a different looking hammer, I can't speak to cocking/decocking/recocking etc. I will say that I don't have interest in a DAO (non striker-fired type) gun - also I read S&W could either sell you the parts or do the work itself to make it use a regular hammer. Whether that is still true or not, again, I'm just repeating a few posts I read.


And regarding the Robar- you're absolutely right, it's a ton of money. And it's really a new gun (I mean you could get another gun of many different types for $415+ etc.) ... My big question is what it does to the parts when they do the NP3 coating- do they resurface each internal part so it's like a new part before getting the new coating? So is it worth it on a 30 year old gun with presumably 30 year old parts? Or will I have it done, then find out, oh you need to replace a ton of stuff inside, and obviously get them coated too if you want to keep it all NP3 etc. So it's just a thought really.

Thanks again, ton of useful info and this is always a great resource to tap into, thanks!
 
Hey hold up one second- got another serious question.

I just realized - there's a half-cock ?

I noticed that the hammer can half-cock. It definitely holds a half-cock position, but the trigger doesn't move as it does during a full cock. What is the reason/benefit/ramifications of this half-cock setting? Thanks again, really, could not be luckier to have you guys to ask questions to.
 
Okay, first to the hammer question. On the xx46 guns, there is a hammer just like the other DA/SA guns -- it just has the thumb spur shaved off it. It works just like you 645 does: rack a round in and it'll be cocked for a short trigger pull. If you elect to de-cock, your first shot will be long DA followed by all short single action pulls.

As to to half-cock on a hammer--
Never a "setting" and not a "user feature." A half cock is yet another fail-safe redundant safety design. The purpose of half-cock is to keep a pistol from unintentional discharge -IF- the sear fails to hold the hammer at full cock.

If you have a very worn sear or sear spring or hammer hook at full cock, the half cock position will (hopefully!) catch a falling hammer BEFORE the pistol goes BANG.
 
Slightly off topic but since the 645 IS stainless steel already, the addition of another finish on top of the original metal would be a waste of money in my estimation. If the $400 is burning a hole in your pocket, why not buy another 645? If one 645 is good, two must be totally awesome!

Just my $0.02.
 
My Sheriff's Office changed from .357 revolvers to the 645. We loved the 645. As much as we loved it, about 4 months before my retirement we changed to the new 4506 pistol. Mine had been to the range once (50 rounds) before I retired. As our contract states when you retire you are given your sidearm. I love the 4506 more than the 645. It has been cleaned, and has a permanent place in my safe. It is a joy to shoot, is accurate, and is built like a tank. Both are fine Gen. 3 pistols. I have three others. Wish I had been able to keep my revolvers as well, but had to sell them to buy the new pistols. You will be happy with the 645.
 
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Hey guys I need some more help-

I ordered new Hogue wood grips- just came in.

I unscrewed the black plastic grips, did my best to clean up the frame area (there's some marks under the grip I obviously didn't see when I bought the gun) -- now I am stuck on what to do. There are square bushings that the screws go into.... I am not really sure what to do here.

Do I need to cut out the screw-holes on the Hogue grips? I am not really sure how to make this work. I would have thought a reputable company like Hogue -- who makes and sells perhaps more grips than anyone-- would have figured this out.

If it's going to be a major project I might have to throw in the towel but if it's not that big of a deal, I'll give it a go. If anyone could help I'd be really grateful, as always- already you gents have been extremely helpful. Ok thanks much!
 
OK Actually we're good- got them done.

When I first encountered this problem, I was thinking to myself, "Am I going to have to redrill these holes? Find a correct bit, somehow not screw it up, and if I DO Screw it Up, I won't be able to return them... this sucks..."

Just as I am about to put back on the plastic black grips, I see my pack of metal files sitting on the ground- LSS, (Long Story Short)- back a few years ago I bought my father a Saiga 12 for Christmas. Also 15 magazines, including 10 factory 5-rounds and 5 ProMags. ALL THE PROMAGS FIT AND WORKED FINE- but the factory mags, 9 of 10 needed (some extensive) filing. So we bought a pack of files, sat down to the table one day, and got to it. Out of nowhere, I had to clean up a mess yesterday and unpacked a storage box that contained the files.... I happened to scan past them on the floor and thought, "Well, there we go- I can just file the holes out to accept the square bushings..." --- and right as I'm about to start filing, I ALSO HAPPEN to see my plastic mallet... and I thought.... "it couldn't be that simple.... could it?"

A few taps with the mallet and presto, they're on. Who knows if that's the proper way to do it, but, it's done!

Thanks again for all the helP!
 
Yes, that, surprisingly, is the correct way.
The square head bushings were a redesign that allowed the bushings to bite into the grip material to help restrain the bushings from backing out when you remove the grip screws.

John
 
ScrapmasterFlex said:
Hi everyone-

I just got a S&W 645 .45ACP and I'm very happy with it. It's 30 years old and not a safe-queen but it's in pretty good condition for said age and 'shooter not safe-er' status.

My question is with the decocker-safety. I am wondering how 'safe' the decocking is.
Click to expand...

As others have stated, the 2nd and 3rd Gen decockers are very safe. I would like to point out something you may not have noticed. With the hammer uncocked, move the safety/decock lever between it's two positions. You will see the hammer move also. When in safe position the hammer is pushed back about 1/8". That is because the central "barrel" portion of the safety/decock is a cam that moves the hammer. No way is the hammer ever going to contact the firing pin when in safe/decock position. Sevens mentioned reports of some 1st Gen safeties shattering and allowing the hammer to contact the unrestrained firing pin. Have never heard of it, but that is what would be necessary to occur for the hammer to contact the firing pin. I have carried 3rd Gen pistols since 1990 and have dropped the hammers countless times. Just do not see that happening.
 
CMB69 said:
As others have stated, the 2nd and 3rd Gen decockers are very safe. I would like to point out something you may not have noticed. With the hammer uncocked, move the safety/decock lever between it's two positions. You will see the hammer move also. When in safe position the hammer is pushed back about 1/8". That is because the central "barrel" portion of the safety/decock is a cam that moves the hammer. No way is the hammer ever going to contact the firing pin when in safe/decock position. Sevens mentioned reports of some 1st Gen safeties shattering and allowing the hammer to contact the unrestrained firing pin. Have never heard of it, but that is what would be necessary to occur for the hammer to contact the firing pin. I have carried 3rd Gen pistols since 1990 and have dropped the hammers countless times. Just do not see that happening.
Click to expand...


Thank you very much, I very much appreciate it and see what you mean and of course feel better knowing the safety factor is so high- Let me clarify if I may,

I was not so concerned per se with the idea it could fire while on safe or even 'off-safe' with the hammer down. I was concerned with the process of *actual decocking* causing an accidential detonation. I don't think this is properly called a slamfire, although I believe you would find people addressing it as a slamfire even though I am pretty sure that is not the correct terminology, a slamfire is a separate event. My reason for this fear was, for a while I owned a Sig P226 MK25 (and I loved it - absolutely loved it- had to sell it and a few other firearms awhile back for an emergency vet bill, but would not have sold it otherwise) and I THINK I remember reading once something along the lines that the SIG decocker had some sort of specific, or extra, or perhaps even additional/redundant, part or system or process during decocking which made it nearly impossible to have a round detonate during decocking, but some other brand or brands were slightly-to-much more susceptible to this happening because of the way the decocker worked. (Now this was a few years ago, I can't even remember the specifics let alone which brand firearm it was listing or anything). So I just wanted to make sure, especially in light of the fact this is 30 years old, I wasn't going to be treated to a BOOM sometime when I decocked the gun not-expecting-it.


Also- I figure I should show this bad boy off, this is what I have, I recently added the grips. Shown with my EDC G27 Gen 4 BFG.
 

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I have a 459 that is the same setup as your 645 in the decocker area.

I understand your reservations.... It takes getting used to, to move a lever, watch the hammer fall at "full speed" and listen to a metallic snap as it hits something without flinching a little and expecting the gun to fire.....especially with a round in the chamber while all of this is happening.

Something that put my mind at ease was closely watching the workings inside the end of the slide as I used the decocker lever while the hammer was fully cocked. You will see that as you begin to slowly move the lever the cam attached to the lever rotates into a position directly between the about to fall hammer and firing pin. The hammer falls and sits against the cam rather than against the firing pin.

As someone else stated earlier, the firing pin is locked in place anyhow because the trigger isn't being pulled and couldn't strike the primer even if the firing pin was hit.....a redundant safety.

Do this several times in "slow motion" and you'll see what I'm talking about.

Even though the decocking process looks unsafe and sounds unsafe, it's actually very safe lol.

Take Care!
Lee
 
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