S &W 686 question

[Rmiked]

You are correct. With gun empty and trigger pulled I can see firing pin from side. After releasing trigger forward until reset, the hammer (and pin since connected) pulls back into frame. That was very helpful.

[Jim Watson]

Early Smith & Wesson Hand Ejectors (and late top breaks) depended entirely on the rebounding hammer. At the time that was thought safe enough for fully loaded carry.
The Colt Positive Safety action of about 1908 was the first revolver with a hammer block internal safety in addition to the rebound.

Smith followed suit with what is known as the "flag" hammer block. It worked well when in good condition but could get stuck disengaged. This is thought to be what happened in WWII when a Navy issue revolver was dropped on a steel deck and fired, killing a sailor who had the misfortune to be in the wrong place. Smith & Wesson hastily designed a new transfer bar cammed up and down instead of spring loaded in and out. They installed it on all new guns 1945 to date and retrofitted all the military revolvers they could get back in.
I have not heard of any program to update commercial guns in private hands, you have the rebound only or flag safety as manufactured. S&W board experts will recommend you treat a pre-1945 Smith like a SAA and keep an empty chamber under the hammer. No degree of care and maintenance is considered adequate to ensure 21st century safety standards.

In the low end of the market, Iver Johnson came out with the transfer bar and the famous "Hammer the Hammer" advertisement. H&R adopted the design and so did Ruger and Colt. Hopkins & Allen had an ingenious design with the hammer on an eccentric, resting against the frame until the trigger was pulled. Safe, but not sturdy and it did not compete well against transfer bar guns.

[Malamute]

Good post, though id mention that

Smith & Wesson hastily designed a new transfer bar

isnt technically correct. The hammer block doesnt function like a transfer bar. Transfer bars fill in a gap between the hammer and firing pin to transmit or transfer the hammer blow to the firing pin. Hammer blocks do not do that, or serve any function in firing, only block the hammer from moving forward when at rest.

Not a big deal, only mentioning it for possible future reference when next time someone says "Smith went to transfer bars......" because they read it on the net, when it was likely a brain glitch in writing.

[Rmiked]

So does my 1986 SW 686 use a hammer block that is effective against firing if dropped? Or should I treat my pistol with an empty chamber under the hammer? I verified after resetting the trigger, the hammer does resist forward movement.

I am a little confused now reading (from Mr Watson):

you have the rebound only or flag safety as manufactured. S&W board experts will recommend you treat a pre-1945 Smith like a SAA and keep an empty chamber under the hammer. No degree of care and maintenance is considered adequate to ensure 21st century safety standards.

[Jim Watson]

Sorry, Malemute, my keyboard and thoughts were out of phase. The Navy accident led to a redesigned hammer block.

Sorry Rmiked, my comments apply only to pre-1945 guns. Your 1986 is as safe from being dropped as a revolver can be made.