[Watchman]

Ok people, I need some advice.

Someone tell me when "hammerblock" saftey devices came about and who invented them ?

When did they become standard issue on revolvers ?

I seem to remember when I was a kid that none of my revolvers had them, then sometime in my teenaged years they seemed to become commonplace on both revolvers and semis.

Any info would be appreciated.

Thanks...

[Mike Irwin]

S&W introduced its first hammer block around World War I or so.

It was redesigned during World War II to correct some deficiencies, and took on the form we know today.

As for other companies?

Beats me.

Iver Johnson company introduced the first widely used transfer bar safety system around 1890-1895, and advertised it with the famous "Hammer the Hammer!" ads.

[4v50 Gary]

I think Mossberg had the first "transfer" bar.

[dfariswheel]

The hammer block first appeared in the 1890's on the Iver Johnson, Colt and Smith & Wesson revolvers.

Iver Johnson's was an early form of the modern transfer bar ignition system, and they advertised their guns with the "Hammer the hammer" safety slogan.

The early Colt double action, swing out cylinder revolver had the first true hammer block, and S&W incorporated one in their first swing out revolver, a few years later.

To be exact, these safeties were actually rebound/blocks. When the trigger was allowed to return after firing, the hammer was moved back, (rebounded) away from the cartridge, and then blocked from moving forward until the trigger was pulled again.

The earlier Colt DA's also had an additional actual hammer block. This was a lever that also blocked the hammer from moving forward until the trigger was pulled. It wasn't until WWII that S&W incorporated this type of block into their guns.

[Mike Irwin]

"I think Mossberg had the first "transfer" bar."

In what?

Rifles or shotguns? I find that a little hard to believe.

The only handgun Mossberg ever made was the Brownie, in the teens and 1920s, I believe.

IJ's transfer bar isn't a hammer block in the sense that the hammer is never blocked from anything.

Dfarris,

As for S&W, the 1899 Military & Police appears to have had a rather different interior with no rebound slide, and thus no "hump" on the rebound slide that served as a hammer block.

The double-action breaktops didn't have any provision for a rebounding hammer, either, as far as I can tell.

I'm not sure when the rebound slide was adopted, but it may have been with the 1903 revisions.

[E357]

I thought that the S&W hammer block was introduced at the request of the Brazilan government contract during the 1920's. I am sure this statement will get me in trouble - I don't think it serves any real purpose in a S&W revolver. I am not talking about the Ruger/Taurus etc. transfer bar safety device.

Elliot

[Mike Irwin]

E357,

Nope.

The original sideplate-mounted hammer block was first installed on S&W revolvers in the teens. I've got a 1917 vintage .32 Hand Ejector with the sideplate hammer block.

The modern hammer block, which looks like a piece of flat bar stock with an "L" bent into it, was introduced during WW II when it was found that the old-style hammer block could become inoperative due to dirt, neglect, etc., and allow the revolver to fire if the gun is dropped. Supposedly a US Navy sailor was killed in this manner, which prompted the change.

The new hammer block is much more sure in that manner. If it gets stuck in either the "on" or "off" position, the gun becomes pretty much impossible to operate.

Brazilian contract guns actually have BOTH types of hammer blocks.

The Brazilian guns were delivered in two distinct bunches -- those delivered in the 1930s before WW II, and which incorporate the old-style hammer block (My Brazilian model is one of these), and those delivered in 1946/47, which incorporate the new style hammer block.

I have to agree with you that the necessity of the hammer block bar is, at best, dubious, but it does protect against a crushing blow against the hammer firing the gun.

Happily, though, it is one of the few safety mechanisms in handguns today that has absolutely no effect on the felt trigger pull.

The old-style sideplate hammer block could have an effect on the felt trigger pull.

[CMcDermott]

Watchman

You are probably thinking of Ruger putting a transfer bar action in their "New Model" single-action revolvers, which happened around 1973-74. The "Old Model" Rugers have three screws through the frame and have a half-cock notch; the "New Model" revolvers use two pins through the frame and doesn't have a half-cock notch, which means they are a pain to load/unload. You can still send the "Old Model" revolvers into Ruger to have them back-fitted with a transfer bar, though be sure to keep the old parts (They'll still fit and can be put back in) for collecter interest and guys like me that don't like what transfer bars do to the trigger pull.

[bountyhunter]

I thought that the S&W hammer block was introduced at the request of the Brazilan government contract during the 1920's. I am sure this statement will get me in trouble - I don't think it serves any real purpose in a S&W revolver.

It is a redundant safety to the one provided by the hammer tail/rebound slide blocking action. If the gun is dropped on the hammer, that piece on the hammer could shatter and the FP on the hammer would ignite the round... and the muzzle would be pointed upward.

Obviously, if you don't drop your guns on their hammers, you don't need a redundant safety system to prevent an AD. I take them out of my comp guns just because the rattling annoys me.

[Jim K]

On S&W revolvers with an inoperable or missing hammer block, dropping the gun on the hammer can either crush the hammer and frame enough to fire (the cause of the Navy accident), or shear the hammer pin, again allowing the gun to fire. The hammer block prevents firing in both cases. The new hammer block is "positive", that is, it must move into the blocking position or the gun is inoperable. (I do not recommend removing the block; a drop of oil prevents rattling.)

S&W actually used two styles of hammer block before the current one. Both were in the sideplate and both acted as their own springs. One was controlled by a plunger in the sideplate which was operated by the back of the hand. The newer one had a tab on the block which mated with a slope on the hand so the hand coming up forced the block inward. The problem with both was that if the block spring broke or the block stuck in the "in" position, it ceased to function; it was not forced to engage.

The Colt Positive Safety goes back to 1905; in fact that is what the word "Positive" in Colt DA revolvers refers to. It is "positive" in that the trigger cannot move forward until the block operates. If the block sticks, the gun is inoperable.

Jim

[Kaylee]

The Colt Positive Safety goes back to 1905; in fact that is what the word "Positive" in Colt DA revolvers refers to. It is "positive" in that the trigger cannot move forward until the block operates. If the block sticks, the gun is inoperable.

I gotta admit, that safety was the one thing I really REALLY liked inside grampa's Police Positive. Icky as I think the bolt release setup is, the postive safey was just a SO much more elegant and user-invisible setup than the transfer bar on my modern Vaquero..

so um.. what's this about them sticking? Was it ever a common problem?
(Heck, you can say "if X sticks, the gun is inoperable" about MOST of the moving parts in any firearm.)

-K

[Watchman]

Thanks all for the replies.

So....

can we safely say that the hammer blcock as we know it came about sometime around WW2 ?

I seem to remember lots of S&W revolvers that still had the firing pin on the hammer back in my youth. I think that they did not have any otehr system on them other tham keeping the hammer on a empty chamber. Is that correct ?

[dfariswheel]

Sorry, no to both questions. You missed the point.

All double action Colt and S&W revolvers made after the 1890's had one type or or another of a hammer block device that prevents firing unless the trigger is pulled.
There were a variety of types used, and additions to the basic devices, but they all had something.

Whether the firing pin is on the hammer or in the frame has nothing to do with the hammer blocks.

[Mike Irwin]

"All double action Colt and S&W revolvers made after the 1890's had one type or or another of a hammer block device that prevents firing unless the trigger is pulled."

Farris,

I don't know about Colt, but that is NOT the case with Smith & Wesson.

Many of the old-style breaktops stayed in production, such as the .44 Double Action (New Model Navy) and a couple other large frame double actions, and the smaller .38 Double Actions Fourth, Fifth, and Perfected Models all used designed that made carrying an empty chamber under the firing pin a necessity.

[dfariswheel]

You're right, I should have said all NEW DA swing-out cylinder designs had some kind of hammer block device after the 1890's.