S&W used a frame mounted firing pin in the K-22 from the beginning. They now use a very similar firing pin in all revolvers. I wonder why they didn't make the switch to frame mounted firing pins in center fire revolvers much earlier?
Why hammer nose?
- Thread starter tatume
- Start date
Register to hide this ad
Green Frog
Member
I’ve wondered about that as well, but there was at least one model that had a frame mounted firing pin from the beginning, the Model 53. I remember an article in one of the gun rags from the ‘60s or ‘70s where the writer was trying to wring more accuracy out of a CF competition revolver (maybe for PPC?) and used a Model 53 frame for the donor in his build. It was never mentioned again that I saw, so there must not have been that much advantage.
Froggie
Froggie
wheelgun28
Member
As a wag, frame mounted is a disadvantage, more parts, more expense, more things to go wrong?
Also, change is scary to most people. Looks, flat faced hammers are as elegant as those with firing pins.
Dont fix things that arent broke...
Also, change is scary to most people. Looks, flat faced hammers are as elegant as those with firing pins.
Dont fix things that arent broke...
If you go back to the early days of American revolvers, you will see the hammer mounted firing pin was the standard. It is just the way it was done. S&W's hand ejector hammers were actually an improvement on the common hammer. The design allowed it to pivot nicely to line up with the channel through the recoil shield as it came forward in an arc. The rebounding hammer had significant advantages, especially for safely carrying a fully loaded cylinder. It was successful. Why change what works?
Here's a picture of two early Colt's hammers.
Here's a picture of two early Colt's hammers.
Sistema1927
US Veteran
I, for one, am glad that they didn't.
DWalt
Member
Colt adopted the firing pin in the frame design for its .357 Magnum revolvers in the mid-1950s. I suppose the reason was that the Colt engineers thought it was safer for use with high pressure cartridges. But I don't know the reason.
The hole in the hammer channel for the hammer mounted firing pin was large. So with the much higher pressure cartridge, there was a great tendency for primers to flow back into the hole and jam the cyl.
In their single action model the fixed firing pin was changed to a floating firing pin (similar to S&W) in 1960, but still mounted on the hammer.
Because of the added agility of the pin, the firing pin hole could be smaller with tighter tolerances that solved the flow back issue.
In their single action model the fixed firing pin was changed to a floating firing pin (similar to S&W) in 1960, but still mounted on the hammer.
Because of the added agility of the pin, the firing pin hole could be smaller with tighter tolerances that solved the flow back issue.
I know you know Froggie, but for the benefit of those who are not familiar with the M53, that centerfire .22 also had inserts for the cylinder in order to shoot .22 rimfire cartridges and an additional cylinder chambered in .22 LR was available as well.
StrawHat
Member
Kevin
Ummm, 1870?
The reference to 1970, though clearly a typographical mistake, is interesting.
The Ruger Blackhawk single action always had a floating firing pin mounted in the frame and a flat face hammer. But the old 3 screw model did not have a rebounding hammer, so, like the SAA, it was not safe to carry with a full cylinder. It was in the early 1970s that Sturm, Ruger decided to add the transfer bar, which receded and prevented the hammer from having contact with the firing pin unless the trigger was in the full rearward position. Thus, the New Model (in 1974, I believe) was enabled to safely carry six rounds in the cylinder.
Hammer mounted firing pins provided dead-on reliability in the age of black powder cartridges. In the case of extreme fouling or a burst primer, a frame mounted firing pin with a tiny return spring could easily seize up in the forward position, tying up the revolver.
In contrast, when hi-speed 22 LR cartridges were developed, they were prone to case failures, having a tendency to split lengthwise or crack open from the firing pin impact. The danger was not black powder fouling (obviously) but, rather, escaping gas under high pressure. That's why S&W used not only the frame mounted firing pin but also recessed chambers to enclose the case rim.
In contrast, when hi-speed 22 LR cartridges were developed, they were prone to case failures, having a tendency to split lengthwise or crack open from the firing pin impact. The danger was not black powder fouling (obviously) but, rather, escaping gas under high pressure. That's why S&W used not only the frame mounted firing pin but also recessed chambers to enclose the case rim.
Kevin,
Well said. But just so no one gets the wrong idea. Although the Colt did keep the rebounding floating pin from resting against the cartridges or rubbing on primers, it offered no other safety or hammer block, i.e., block the hammer from moving forward and firing a cartridge. The initial rebounding S&W hammer improved upon that but still was not "fool proof" thru two hammer block safety improvements, until the WWII final design of the 3rd type, the sliding bar hammer block safety still in use to this day.
Ruger's transfer bar hammer safety system has been "fool proof" from the git go when introduced in 1973. Albeit it works in reverse of the S&W design and does not rebound/block the hammer. When at rest it can not contact the floating firing pin mounted in the frame UNLESS the transfer bar is inserted between the hammer and firing pin by pulling the trigger. It's the transfer bar that actually rebounds (recedes as Jack posted above) when the trigger is released.
The system saves Ruger over a million dollars a year in lawsuits that they used to budget for the "ambulance chasers" during the old model years preceding 1973. Interestingly although the Colt SAA has no modernized safety system, they are not plagued with lawsuits, presumably because of its much higher market price point.
Well said. But just so no one gets the wrong idea. Although the Colt did keep the rebounding floating pin from resting against the cartridges or rubbing on primers, it offered no other safety or hammer block, i.e., block the hammer from moving forward and firing a cartridge. The initial rebounding S&W hammer improved upon that but still was not "fool proof" thru two hammer block safety improvements, until the WWII final design of the 3rd type, the sliding bar hammer block safety still in use to this day.
Ruger's transfer bar hammer safety system has been "fool proof" from the git go when introduced in 1973. Albeit it works in reverse of the S&W design and does not rebound/block the hammer. When at rest it can not contact the floating firing pin mounted in the frame UNLESS the transfer bar is inserted between the hammer and firing pin by pulling the trigger. It's the transfer bar that actually rebounds (recedes as Jack posted above) when the trigger is released.
The system saves Ruger over a million dollars a year in lawsuits that they used to budget for the "ambulance chasers" during the old model years preceding 1973. Interestingly although the Colt SAA has no modernized safety system, they are not plagued with lawsuits, presumably because of its much higher market price point.
I'm just enjoying reading all this stuff. Much of it I did not know. Very interesting.
Personally I think it was an improvement when S&W moved from a hammer nose to a frame mounted firing pin. First it is way easier to change out. Another is less apt to have a interference problem. The tip of the hammer nose has to make a long arc and it all has to go perfectly for that tip to enter the frame work past its frame cuts to go through the hole in the firing pin bushing to deliver 100% of the hammers force. With a frame mounted pin all it needs is to be driven straight forward by the hammer face overcoming the little tiny weak spring needed to keep it popped back out of the way when the cylinder cycles.
CAJUNLAWYER
Member
I suspect it was something as simple as the fact Smith started out making revolvers with hammer mounted firing pins and didn't see the need to go through the expense of re tooling to a frame mounted firing pin until the machines wore out at which time they went with the frame mounted pin. Ruger, starting later, went with the frame mounted pin from the get go.
shadowriders600
Member
- Joined
- Mar 25, 2018
- Messages
- 8
- Reaction score
- 12
M-53 .22 Jet Magnums had two frame mounted firing pins and a selector on the hammer nose.
Sent from my iPad using Tapatalk
Sent from my iPad using Tapatalk
I suspect it was something as simple as the fact Smith started out making revolvers with hammer mounted firing pins and didn't see the need to go through the expense of re tooling to a frame mounted firing pin until the machines wore out at which time they went with the frame mounted pin. Ruger, starting later, went with the frame mounted pin from the get go.
Ruger's first revolver was the .22 LR Single Six, a scaled down single action. The frame mounted firing pin was the accepted method for most .22 rimfire revolvers. Ruger's second revolver was the .357 Blackhawk. The .357 was the high pressure handgun cartridge of the day. Some firms, like Christy's (spelling?), would bush the firing pin hole in Colt Single Action Army revolvers when they were converted to .357. So, Ruger went with the frame mounted firing pin in all of their revolvers, except for the black powder Old Army.
Last edited:
Frame mounted pins can "goo up". BTDT.
