Do all C prefix S&W K frames revolvers use hammer blocks?
- Thread starter JellyJar
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stu1ritter
Member
Indeed, it is the final safety device. There should be a small pin protruding from the rebound slide that guides the eye end of the hammer block. Some take it out thinking it helps a lighter, smoother double action pull but the hammer block can be polished to avoid any possibility of friction. It is a necessary safety against a loaded revolver being dropped on the hammer.
Stu
Stu
Thanks for the quick reply. I could not get the side plate off because I don't have the appropriate screwdriver. However, getting a flashlight and looking between the hammer and frame while it was cocked I can now see the hammer block. It dose not rattle when you shake it so I thought it wasn't there.
Also, the person who sold it to me said it was pre Victory model. He was wrong. He apparently did not see the C prefix before the serial number.
I paid $360 for it and it is in excellent condition so I think I came out just fine.
Thanks
JJ
Also, the person who sold it to me said it was pre Victory model. He was wrong. He apparently did not see the C prefix before the serial number.
I paid $360 for it and it is in excellent condition so I think I came out just fine.
Thanks
JJ
stu1ritter
Member
$360 for a C prefix M&P is indeed a very nice price. I have a C prefix snub and really enjoy shooting it.
Stu
Stu
Driftwood Johnson
Member
Howdy
First off, you need more than the correct screw drivers to get the side plate off of a S&W revolver. There is a trick to it, which we can talk about another time. If you try to pry off the side plate, you will make a mess of things.
S&W has been putting hammer blocks in their revolvers for a very long time. The very first Hand Ejectors had no hammer blocks. But at some point S&W realized that the rebounding hammer was not safe enough, and a hammer block was needed in addition to the rebounding hammer.
As far as I know, there have been three different types of hammer blocks installed in S&W revolvers. This is the first type. It is from a 38 M&P Target Model from 1917. The hammer block is the long, thin part sitting in the narrow slot in the side plate. Notice the spring loaded pin sitting sideways, poking through a hole in the side plate. I have positioned the hand (pawl) of the revolver in the position it would be to operate the hammer block. As the hammer rotated back, the hand was pushed up to rotate the cylinder. The sloped surface on the side of the hand shoved the pin in, which in turn pulled the hammer block into the side plate. The tip of the hammer block was thus withdrawn from between the hammer and the frame, allowing the hammer to fall all the way to fire a cartridge.
This is the second style of hammer block. This is the style that was used up until 1944. This style is simpler (probably less expensive to manufacture). The hammer block is a piece of spring steel, sitting in a slot in the side plate and staked to the side plate at the bottom of the hammer block. There us a ramp built onto the side of the hand. As the hand rose, the ramp would engage the horizontal tab on the hammer block, causing it to withdraw into the side plate so the hammer could fall all the way.
This style of hammer block failed when a soldier was killed by a Victory Model that fell to the deck of a warship. The gun discharged, killing the soldier. What apparently happened was the gun was gummed up with Cosmoline. The hammer block was stuck in the withdrawn position. When the gun fell on the hammer spur, the hammer block was not in its proper position and the gun fired, killing the sailor.
In this photo you can see the bump on top of the rebound slide has pulled the hammer back slightly. That is the rebounding feature of the hammer of all S&W revolvers built since 1905. What probably happened in this case is when hammer spur struck the deck, the thin section of the hammer down near the rebound slide probably failed, freeing the hammer to be shoved all the way forward. The hammer block was not there to do its job, and the gun discharged. An alternate scenario is the stud the hammer rotates on may have broken, allowing the hammer to fall all the way forward.
This is the third style of hammer block. It was designed in a hurry after the sailor was killed with the earlier type of hammer block. This hammer block does not rely on springs to operate, it uses the positive mechanical action of the rebound slide to operate the hammer block. This hammer block also sits in a slot in the side plate, but it is free to slide up and down. The hammer block is the long, thin, slanted part. It is shown in its normal position, blocking the hammer from moving all the way forward.
When the trigger moves backward, either because the hammer is cocked or because the trigger is pulled, the rebound slide moves backwards too. The pin mounted in the side of the rebound slide pulls the hammer block down, so the hammer can fall all the way. When the trigger is released, the powerful spring in the rebound slide pushes the rebound slide and the trigger forward. The pin in the rebound slide then pushes the hammer block back up to its normal position, blocking the hammer from falling all the way.
All Smith and Wesson revolvers built after 1944 have this last type of hammer block, right up to the present day.
Answering the original question, the C Serial Prefix revolvers, began with C1 in 1948. So all C Serial Prefix revolvers will have this style of hammer block in them. The serial number range for C Serial Prefix revolvers for 1948 through 1951 ran from C1 to C223998. C36XX was probably fairly early in that range.
Sometimes someone will remove the hammer block in the mistaken belief that it will make the trigger pull smoother. This is a big mistake.
To make sure it is there without removing the side plate, cock the hammer very slowly and peer inside. You should see the hammer block moving down.
It sounds like you have already done this.
First off, you need more than the correct screw drivers to get the side plate off of a S&W revolver. There is a trick to it, which we can talk about another time. If you try to pry off the side plate, you will make a mess of things.
S&W has been putting hammer blocks in their revolvers for a very long time. The very first Hand Ejectors had no hammer blocks. But at some point S&W realized that the rebounding hammer was not safe enough, and a hammer block was needed in addition to the rebounding hammer.
As far as I know, there have been three different types of hammer blocks installed in S&W revolvers. This is the first type. It is from a 38 M&P Target Model from 1917. The hammer block is the long, thin part sitting in the narrow slot in the side plate. Notice the spring loaded pin sitting sideways, poking through a hole in the side plate. I have positioned the hand (pawl) of the revolver in the position it would be to operate the hammer block. As the hammer rotated back, the hand was pushed up to rotate the cylinder. The sloped surface on the side of the hand shoved the pin in, which in turn pulled the hammer block into the side plate. The tip of the hammer block was thus withdrawn from between the hammer and the frame, allowing the hammer to fall all the way to fire a cartridge.
This is the second style of hammer block. This is the style that was used up until 1944. This style is simpler (probably less expensive to manufacture). The hammer block is a piece of spring steel, sitting in a slot in the side plate and staked to the side plate at the bottom of the hammer block. There us a ramp built onto the side of the hand. As the hand rose, the ramp would engage the horizontal tab on the hammer block, causing it to withdraw into the side plate so the hammer could fall all the way.
This style of hammer block failed when a soldier was killed by a Victory Model that fell to the deck of a warship. The gun discharged, killing the soldier. What apparently happened was the gun was gummed up with Cosmoline. The hammer block was stuck in the withdrawn position. When the gun fell on the hammer spur, the hammer block was not in its proper position and the gun fired, killing the sailor.
In this photo you can see the bump on top of the rebound slide has pulled the hammer back slightly. That is the rebounding feature of the hammer of all S&W revolvers built since 1905. What probably happened in this case is when hammer spur struck the deck, the thin section of the hammer down near the rebound slide probably failed, freeing the hammer to be shoved all the way forward. The hammer block was not there to do its job, and the gun discharged. An alternate scenario is the stud the hammer rotates on may have broken, allowing the hammer to fall all the way forward.
This is the third style of hammer block. It was designed in a hurry after the sailor was killed with the earlier type of hammer block. This hammer block does not rely on springs to operate, it uses the positive mechanical action of the rebound slide to operate the hammer block. This hammer block also sits in a slot in the side plate, but it is free to slide up and down. The hammer block is the long, thin, slanted part. It is shown in its normal position, blocking the hammer from moving all the way forward.
When the trigger moves backward, either because the hammer is cocked or because the trigger is pulled, the rebound slide moves backwards too. The pin mounted in the side of the rebound slide pulls the hammer block down, so the hammer can fall all the way. When the trigger is released, the powerful spring in the rebound slide pushes the rebound slide and the trigger forward. The pin in the rebound slide then pushes the hammer block back up to its normal position, blocking the hammer from falling all the way.
All Smith and Wesson revolvers built after 1944 have this last type of hammer block, right up to the present day.
Answering the original question, the C Serial Prefix revolvers, began with C1 in 1948. So all C Serial Prefix revolvers will have this style of hammer block in them. The serial number range for C Serial Prefix revolvers for 1948 through 1951 ran from C1 to C223998. C36XX was probably fairly early in that range.
Sometimes someone will remove the hammer block in the mistaken belief that it will make the trigger pull smoother. This is a big mistake.
To make sure it is there without removing the side plate, cock the hammer very slowly and peer inside. You should see the hammer block moving down.
It sounds like you have already done this.
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