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Revolver transfer bar question
- Thread starter Mikey
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Chris
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As early as the 50's on some models, and as late as the 70's on others.
Anything in the 90's would have it.
I would skip the Taurus guns. Just a personal opinion.
Anything in the 90's would have it.
I would skip the Taurus guns. Just a personal opinion.
They have been around in various forms since the early part of the 20th century. Can't give you specifics, but I have seen/heard of them waaaaayyy back.
Semi autos with them go back to that same era. I saw a 1917 Warner-Davis .32 semi that has a block in it.
Semi autos with them go back to that same era. I saw a 1917 Warner-Davis .32 semi that has a block in it.
Thanks, I thought they went way back but just wanted to be sure.
I know i should skip the Taurus but I can get it real cheap, it is just hard to say no, I am trying to talk my self out of it and put the money towards another Smith. (Taurus model 85 or a Smith 442 or 642)
+1
Distinguish between a transfer bar, which is used to complete the path from a flat-faced hammer and a frame-mounted firing pin, and a hammer block, which is a device that, when in the "safe" orientation, prevents the hammer from falling far enough to cause the firing pin to emerge from the recoil shield hole (whether the pin is hammer-mounted or frame-mounted).
Transfer bars have been used for a long time for Colt revolvers and for an equally long time for Smith & Wesson rimfire revolvers. They have been used only recently for S&W centerfire revolvers.
A frame-mounted firing pin is considered a "safety" item only insofar as it is one engineering solution to the issue of keeping the hole through which the pin moves as small as possible (so as to leave as little of the primer cup or case unsupported as possible).
I believe that some designs later incorporated a means of causing the transfer bar to recede when the trigger was not pressed, thereby effectively "disconnecting" the hammer from the pin, but am not really familiar with such designs.
The hammer block has been standard fare with S&W revolvers more or less since 1896. In fact, today there are two independent hammer blocks: the rebound slide (part of the original design) and the nominal hammer block (added in 1947 and which actually never performs any function so long as the rebound slide is functional). These devices prevent the revolver from firing if a cocked hammer is dropped by a sear failure or jar-out, a push-off, a twig hitting the trigger, or any event other than someone pulling the trigger and keeping it pressed for the entire time of hammer fall.
Transfer bars have been used for a long time for Colt revolvers and for an equally long time for Smith & Wesson rimfire revolvers. They have been used only recently for S&W centerfire revolvers.
A frame-mounted firing pin is considered a "safety" item only insofar as it is one engineering solution to the issue of keeping the hole through which the pin moves as small as possible (so as to leave as little of the primer cup or case unsupported as possible).
I believe that some designs later incorporated a means of causing the transfer bar to recede when the trigger was not pressed, thereby effectively "disconnecting" the hammer from the pin, but am not really familiar with such designs.
The hammer block has been standard fare with S&W revolvers more or less since 1896. In fact, today there are two independent hammer blocks: the rebound slide (part of the original design) and the nominal hammer block (added in 1947 and which actually never performs any function so long as the rebound slide is functional). These devices prevent the revolver from firing if a cocked hammer is dropped by a sear failure or jar-out, a push-off, a twig hitting the trigger, or any event other than someone pulling the trigger and keeping it pressed for the entire time of hammer fall.
RKG great info thanks,
I dont recall seeing any new hammer mounted firing pins from smith or any of the big manufactures, is the design just not as good as frame mounted versions?
and
Would an older smith with a hammer mounted pin be "less safe"? Like an older model 60.
I dont recall seeing any new hammer mounted firing pins from smith or any of the big manufactures, is the design just not as good as frame mounted versions?
and
Would an older smith with a hammer mounted pin be "less safe"? Like an older model 60.
Chris
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Nah, Hammer Mounted Pins are just a grat way to know that the gun was built "in the good ol days". (^_^) I have a mid '60's Model 10 with a pin on hammer that is simply a better gun all around out of the box than anything I know of today. I suspect that some others in my collection would be just as good if I opened them up and gave them a really good cleaning.
There is just something about the mid-century guns that just feel "crafted with care" that I don't get with guns made today. Maybe it is the finish, maybe it is the final machining. Whatever it is, I just like the way they feel.
There is just something about the mid-century guns that just feel "crafted with care" that I don't get with guns made today. Maybe it is the finish, maybe it is the final machining. Whatever it is, I just like the way they feel.
A hammer-mounted pin that is fixed (such as the Model P Colt) necessarily requires an enlarged hole for the pin to pass through. The reason is that the fixed pin cannot travel in a straight line, but rather follows the curve of the hammer arc. By definition, the enlarged pin hole means that more of the primer is unsupported than is necessary, though I've never heard of a problem with low pressure rounds (such as are fired from Model Ps).
You will notice that the pins on S&W centerfire revolvers seem to be loose. So much so, that occasionally a newbie will bring you their new S&W revolver and ask if the loose pin is a defect in need of repair. In fact, the ability of the pin to rotate (to some degree) in a vertical plane allows it to travel linearly through the pin hole and thus to have a pin hole with minimum tolerance.
Another tribute to the mechanical acumen of one Daniel B. Wesson.
You can divide the period of S&W manufacture very roughly into four periods:
Prior to about 1980.
Between about 1980 and 1990.
From about 1990 until the recent conversion to CNC processes.
The current CNC regime.
It is little known, but quite true, that before the CNC regime, S&W did not have any dimensioned factory drawings for its revolvers. Parts were basically made by drop forging, followed by some coarse machining and then some very precise hand fitting. Some of the critical areas are cylinder to crane, extractor to cylinder, cylinder stop, rebound slide, and sear.
Where attention was paid to quality (the first and, largely, the third periods), the result was works of art. Where not (the second period), the result was revolvers most of which were in need of a post-purchase trip back to the factory to finish what should have been done pre-first-sale.
I have no real experience with the current regime. In theory, parts should now by more uniform, diminishing the need for hand fitting and increasing the interchangeability of parts, but, as I say, I cannot confirm that this objective has been met.
Wow I have so much to learn.
Living in western mass I have known a bunch of people who have worked at Smith, One of them who I do not have much of a relationship with is (I think) a shooter I will call it, meaning he is one of the guys who test fires every gun made. Another guy who I used to work with was a machinist, he has many times told me that the quality has improved considerbly since the last sale of the company and being that he does not work there anymore he talks to others who still do and mentions that the company has a new found "pride".
I recently got a new model 620 and have to say that it is a great gun and the "fit and finish" is very good (.003 cylinder gap, smooth trigger pull, relocated cylinder notches for greater strenght etc...). Only bad thing I have noticed so far is there are a few minor imperfections in the finish which somebody with more experience then myself would have to look at to tell me if they are normal or a screw-up.
Living in western mass I have known a bunch of people who have worked at Smith, One of them who I do not have much of a relationship with is (I think) a shooter I will call it, meaning he is one of the guys who test fires every gun made. Another guy who I used to work with was a machinist, he has many times told me that the quality has improved considerbly since the last sale of the company and being that he does not work there anymore he talks to others who still do and mentions that the company has a new found "pride".
I recently got a new model 620 and have to say that it is a great gun and the "fit and finish" is very good (.003 cylinder gap, smooth trigger pull, relocated cylinder notches for greater strenght etc...). Only bad thing I have noticed so far is there are a few minor imperfections in the finish which somebody with more experience then myself would have to look at to tell me if they are normal or a screw-up.
