Short Throw vs. Long Throw Hammer ?
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Alk8944
US Veteran
It should pretty well be self-explanatory.
Early S&W revolvers, until 1948, had lockwork where the hammer travelled through a greater angular range resulting in a longer hammer fall distance. In 1948 the lockwork was re-designed to shorten the distance the hammer travelled to full cock which resulted in a shorter fall and quicker lock time. This was accomplished by changes in the geometry of virtually every internal part, and changes in hammer and trigger pin positions.
If you can get a pre-war and post 1948 revolver, cock both and compare them side-by-side you will easily see the difference in hammer position and the distance the hammer has to fall when the trigger is pulled.
Early S&W revolvers, until 1948, had lockwork where the hammer travelled through a greater angular range resulting in a longer hammer fall distance. In 1948 the lockwork was re-designed to shorten the distance the hammer travelled to full cock which resulted in a shorter fall and quicker lock time. This was accomplished by changes in the geometry of virtually every internal part, and changes in hammer and trigger pin positions.
If you can get a pre-war and post 1948 revolver, cock both and compare them side-by-side you will easily see the difference in hammer position and the distance the hammer has to fall when the trigger is pulled.
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rburg
Member
You're talking about hammer's on guns made around WWII (really, they were made well before and well after, but the time they intersect is WWII).
Basically, all but 1000 guns before WWII were long action. Except the very early postwar years, the ones after were short action.
The hammers were not interchangeable, except with some pretty dramatic other action changes (geometry). Most of us can't tell by looking at the important parts which is which. The convenient way to tell is by looking at the hammer spur shape. Lucky for us they were different.
We have short and long actions in the most common action sizes and calibers (22s don't have hammer mounted firing pins).
The reason we're interested is usually because we've found a free hammer and want to ID it, or we've broken one and need a replacement. Then it becomes real important to know what we've got or what we need.
There are or seem to be other differences, such as diameter of the pin hole.
Its a problem to buy on the internet because you have the problem of sellers wanting to sell and either not knowing themselves or misrepresenting what they've got. I've heard you should never assign ill intent when stupidity is equally possible.
To educate yourself, look at the photos our posters put up every day. Or better still, buy yourself examples of the guns and study them that way!
Basically, all but 1000 guns before WWII were long action. Except the very early postwar years, the ones after were short action.
The hammers were not interchangeable, except with some pretty dramatic other action changes (geometry). Most of us can't tell by looking at the important parts which is which. The convenient way to tell is by looking at the hammer spur shape. Lucky for us they were different.
We have short and long actions in the most common action sizes and calibers (22s don't have hammer mounted firing pins).
The reason we're interested is usually because we've found a free hammer and want to ID it, or we've broken one and need a replacement. Then it becomes real important to know what we've got or what we need.
There are or seem to be other differences, such as diameter of the pin hole.
Its a problem to buy on the internet because you have the problem of sellers wanting to sell and either not knowing themselves or misrepresenting what they've got. I've heard you should never assign ill intent when stupidity is equally possible.
To educate yourself, look at the photos our posters put up every day. Or better still, buy yourself examples of the guns and study them that way!
Driftwood Johnson
SWCA Member
Howdy
Something else needs to be said about the reason the short throw hammer came about. Because of the design, double action hammer travel must always be greater than single action hammer travel. It is intrinsic to the design. Double action hammer travel can never be the same or less than single action hammer travel.
But with the original long throw design, double action hammer travel was a great deal longer than single action hammer travel. This meant that the hammer spring was flexed a great deal more when firing the revolver in double action mode than when firing in single action mode. But the amount of spring flex needed to fire the gun in single action mode was all that was needed to reliably pop a primer. That meant that all that extra spring flex was unneeded, and made it more difficult to fire the gun in double action mode than needed to be.
By redesigning the lockwork so that the hammer tripped in double action mode with just barely more spring flex than in single action mode, double action firing became easier, as the trigger finger did not have to fight the hammer spring as much as in the long throw design.
It was really about making the revolver easier to shoot in double action mode, it was not so much about reducing lock time.
Something else needs to be said about the reason the short throw hammer came about. Because of the design, double action hammer travel must always be greater than single action hammer travel. It is intrinsic to the design. Double action hammer travel can never be the same or less than single action hammer travel.
But with the original long throw design, double action hammer travel was a great deal longer than single action hammer travel. This meant that the hammer spring was flexed a great deal more when firing the revolver in double action mode than when firing in single action mode. But the amount of spring flex needed to fire the gun in single action mode was all that was needed to reliably pop a primer. That meant that all that extra spring flex was unneeded, and made it more difficult to fire the gun in double action mode than needed to be.
By redesigning the lockwork so that the hammer tripped in double action mode with just barely more spring flex than in single action mode, double action firing became easier, as the trigger finger did not have to fight the hammer spring as much as in the long throw design.
It was really about making the revolver easier to shoot in double action mode, it was not so much about reducing lock time.
PhilOhio
Member
I have quite successfully converted two long-throw WW-II Victory frames to post-war snubbies, using all 1960s vintage nearly new K-frame internals. Pictures were in another thread. Note that I did not mix WW-II vintage parts with 1960s parts. All the latter were compatible with each other. They just went into an earlier WW-II frame, that had been modified in only one way, hammer axis location.
The main issue was to accurately move the hammer axis pin hole forward. I used modern post-war side plates as the "jigs", to mark the holes. Original holes were then welded shut, with surfaces machined flush. Incidentally, the post-war side plates FIT PERFECTLY! ...a real tribute to S&W dimensional control over some 20 years.
The only place I noticed a minor dimensional difference was that a few thousandths had to be removed from the upper edge of one firing pin, to clear the top of the bushed hole in one of the Victory frames.
I've fired both of these guns extensively, and if there were some mysterious compatibility problem, I would know about it by now.
For anybody thinking about something similar, it is not nearly as difficult as it sounds. Beyond moving the hammer pin, your main concern is making sure all the small parts are of the same modern vintage and compatible with each other. As some of the above posters suggest, you might have difficulty mixing new hammers with old triggers, etc.
The main issue was to accurately move the hammer axis pin hole forward. I used modern post-war side plates as the "jigs", to mark the holes. Original holes were then welded shut, with surfaces machined flush. Incidentally, the post-war side plates FIT PERFECTLY! ...a real tribute to S&W dimensional control over some 20 years.
The only place I noticed a minor dimensional difference was that a few thousandths had to be removed from the upper edge of one firing pin, to clear the top of the bushed hole in one of the Victory frames.
I've fired both of these guns extensively, and if there were some mysterious compatibility problem, I would know about it by now.
For anybody thinking about something similar, it is not nearly as difficult as it sounds. Beyond moving the hammer pin, your main concern is making sure all the small parts are of the same modern vintage and compatible with each other. As some of the above posters suggest, you might have difficulty mixing new hammers with old triggers, etc.
TSQUARED
Member
For some unexplained reason I still believe that the Pre WWII S&W's had the smoothest DA trigger pulls albeit long.
10/22
Member
I agree.I'll take a prewar long action over the short any day.
Wow, I was about to say the same thing. Those old actions feel so smooth the extra spring flex talked about just moves everything along soo smoothly you never notice. I have post war K's and a 1905, 4th change M&P .38, built in 1919 that beats even the K's for DA action
Hi Driftwood,
I don't mean to be contradictory but when one observes the backward hammer travel it's just the opposite, further back for single action than double action and therefore a SHORTER hammer fall in DA. This is true for both pre-war long actions and post war short actions. However the difference in backward hammer travel between DA and SA is less in post war short action guns. By looking at the hammer out of the gun it can be seen that the DA sear is engaged sooner by the trigger and the hammer requires further backward travel before the SA hammer notch engages the trigger. It can be seen clearly in this video which shows internal engagement for both SA and DA.
http://www.genitron.com/Basics/Revolver/P2Revolver.html
I realized this when I had a failure to fire in double action so tried single action and FTFs usually will go off because of the farther hammer fall and the additional (heavier) spring flex.
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That is an extremely cool and helpful link, thanks so much!!
I was never quite sure how the single and double action sears exactly functioned. Now I know
