S&W 457 hammer exchange

[tjtoolbox]

I have a S&W 457 , 45acp semi auto. I am going to change out the flush hammer with a serated hammer only because it is what I to decock the firearm, I just changed out the safety to ambi because I am LH. I have done researse about replacment of one for the other and the hammers from all semiauto will fit all other S&W semiauto pistols.

All Comments Welcome

[jimmyj]

Yes, several hammers will fit your Model 457 I know this as I asked the same question in an earlier post

[cmj8591]

Why do you need to use the hammer to decock a 457?

[tjtoolbox]

Originally Posted by cmj8591

Why do you need to use the hammer to decock a 457?

Just a personal preference.

[Fastbolt]

Personal preference is one thing, but maximizing practical safety is another.

When you use the decocking lever to decock the hammer in a 3rd gen pistol in normal, good working condition ...

... The trigger isn't being pulled, so the firing pin safety lever isn't being rotated to lift the firing pin safety plunger, and the firing pin safety plunger is blocking the firing pin from moving.

... The manual safety body has internal machined "shoulders" which rotate down and capture the shoulders of the firing pin, on each side, blocking the firing pin from moving.

... The rear of the manual safety body rotates upward and puts some steel behind the firing pin, preventing the hammer from hitting the rear of the firing pin.

When you decock a 3rd gen by pulling the trigger while trying to hold and lower the hammer spur, you're essentially bypassing all of those mechanical safety features.

Sure, people have been lowering hammers on revolvers and 1911's for many years ... but they've also occasionally been experiencing ND's throughout those years.

Nonetheless, if you're interested in having a spurred hammer installed on the 457 which originally came with a spurless hammer - (and some people do like spurred hammers for carefully thumb cocking a gun into SA for an initial shot, such as for hunting, target shooting, plinking, etc)- then a smith familiar with the TDA S&W's (or a 3rd gen pistol armorer, if you can find one) ought to be able to make the replacement and perform the routine bench/safety checks to confirm any particular spurred hammer will fit and function in your 457.

Presuming the correct "compact" stirrup is installed on the hammer, hammers may be "drop in" assemblies in one respect, but they still require some inspection and checks to make sure they work with the rest of the parts in any particular gun. The Single Action, DA Pick-up & Throw notches of any particular TDA hammer all have to fit and work with the existing sear (nose) and drawbar (corresponding notches).

Sometimes in the "parts is parts" guns not all combinations of all parts might work in all frames/guns, due to normal tolerance stack variations, and normal fit & function ought to be checked by someone who is familiar with how they ought to fit & work.

Just some thoughts.