I was cleaning this one up last weekend and noticed it takes almost no thumb pressure against the back of the hammer in full cock to cause it to release.

In half cock it holds strong against thumb pressure.

This little gun is in overall good condition, is tight at the hinge and latch,times well and functions fine otherwise.

Can anyone tell me what may be the cause of this and what it may take to remedy?

Thanks in advance.

Not the most expensive Antique out there but I have grown quite fond of this one never the less.

If anyone has an idea about this please do let me know.

Sounds like a worn sear. The only way I've repaired that was with a replacement hammer. Others may be along with advice.

What you have is known as push off on the hammer. The hammer should stay cocked in the full cock notch with pressure on the hammer, if not then more than likely the full cock notch on the sear lost its sharpness. Unless you know what you are doing, the full cock notch has to be stoned to bring back the original sharpness. That entails disassembly of the gun and removing the trigger for stoning the full cock notch. I would try and remove the side plate and start with a good cleaning and try that and if it doesn't work, I would take it to a good gunsmith who is familiar with these guns. I had the same problem with mine and I cured the problem with a little stoning. Again, if you do not know what you are doing, you can over stone the sear and cause further problems. Good luck.

Nick

If you have some basic skills on working with metals, you should be able to stone the hammer and the sear if dull. Do it lightly and try it. Might take several times before you get a solid lockup. Broken or chipped sears might also be a problem, so a replacement would have to be found. This is an unsafe situation, so I would not shoot the gun until a fix is done.

Thanks so much for the information guys, just what I was looking for. If I don't have a broken or chipped sear i will try the stone route.

I am a long time free hand knife sharpener and have several stones at my disposal. I have a pretty good feel for angles and the 'feel' for moving small amounts of metal.

Here is a list of stones that I have, please let me know what what you suggest would work best:

Black Hard Arkansas
Translucent Hard Arkansas
Wa****a Arkansas
DMT continuous diamond stones from course to extra extra fine.

I will get some macro photos up of the internals with details of the area mentioned above before I proceed, to make sure we are on the same page.

Thanks again.

Any will work, but you will need a small one with a shape that fits the hammer. Pay particular attention to the angles you are working with and maintain those angles when stoning. You should be able to tell whether the sear or the hammer is dull and only do one at a time and try. When done, there should be no amount of thumb pressure that will push off the hammer, but trigger pull should remain smooth.

I would leave the hammer alone. It is the trigger/sear you want to concentrate your stonning. Find a piece of granate or one of those circular slabs from stone cold ice cream. Three stones you want to have are medium, fine and ceramic. Place the trigger on the slab and start with the medium stone on the slab and stone the bottom portion of the sear from top and work it toward the bottom with a sweep as you come off the bottom. It will take about several sweeps, Keeping the stone on the surface will give you the right angle. Then use the fine stone and then the final stoning would be the ceramic. The sear should be sharp enough that it will cut your fingernail. Do not over sharpen. Most of the time, the sear will have a bit of the end where the sear makes contact with the hammer. Usually the hammers are case hardned but I believe these hammers are not. All in all, you do not have to stone the hammer. There are some other tips but try this for starters. Let me know how you make out.

I took it apart today and found that the hammer had already been worked and, I might add, rather shabily.
It became apparent that the work done to the hammer resulted in the portion that makes full-cock contact with the trigger, sitting at an obtuse angle, which the trigger/sear easily slipped off of.
I decided to clean up what had been done and bring that angle in just a bit.

I started with my fine diamond hone and worked it to extra fine.
This made things much worse. Now I could, with almost no pressure, push the hammer off of the sear.

Upon closer inspection I could see that my stones, at the edges, weren't perfect right angles, but rather slightly rounded so that I wasn't hitting in the corner as I had intended, which only aded to the problem.

I then moved to a mill ******* file, the only tool I had with perfectly square edges, and reworked the area making sure to minimally contact the face of the hammer/sear but rather deepen the base/angle and straighten the overall angle of the sear face.

After a few passes i checked my work and found that it was holding a bit better. With that that I went to work, keeping the same angle and rechecking as I went along.

Now it holds firm. I can push it till my thumb hurts and it won't budge, which makes me very happy.
This left me with a course finish, due to the use of the file, and I am not sure if I should leave it or attempt to polish it.
I am also not sure if I should attempt any work on the trigger, now that it holds so tight or just leave it well enough alone.

Any suggestions for my next step would be great.

Check Brownell's website for the proper shaped stones used for action work. I have a few of their stones and they have sharp angles on them, perfect for sear work. Good luck!

http://www.brownells.com/search/inde...ones&ksubmit=y

__________________
GMC-USN, Retired/1978 to 2001

Remember that you have a 130 plus year old gun there, and it never had a perfect trigger pull when new. If the trigger pull is smooth and takes less than 2 fingers to fire, I would not mess with it more. Your next step is to take it to the range and see if there is enough hammer travel to detonate the primer. When you take material off the hammer, it moves the firing pin closer to the primer, so sometimes the hammer fall is to short, causing light strikes. Make sure your trigger tension screw is tightened all the way and the cylinder locks up tight on every pull of the hammer.

Thanks for the link, these are exactly what I had in my mind's eye as i was working away yesterday.

The trigger pull is great right now.

I never considered the distance between the primer and hammer at full cock.
I was, coincidentally, very careful to minimally touch the 'face' (struggling with proper terminology hear) of the hammer sear while I was filing. Most of the metal removed was removed so as to deepen the facet and straighten it by working the base.
I used a black sharpie to keep track of my contact areas which helped quite a bit.

I do have a question about whether or not this group is case hardened and, if it is, what effect filing will have on the hard surface.
In other words, if it is hardened, will it break through the surface leaving softer metal for the new contact surface?

I think all S&W revolvers back to the Model 1 were case-hardened, but the steel used back then was probably still softer when case-hardened than mild steel today. I doubt that you will shoot enough to wear the hammer out in your lifetime.

Ok great, I'll stop worrying about it then.
I just loaded up and handfull of cartridges this afternoon using triple 7, FFF under a 146grn. Missouri bullet. I'll give it the smoke test next weekend.

Thanks again for the pointers everyone.

I completed the 'smoke' test last week and this little revolver performed flawlessly. Absolutely no push off before, during or after shooting.
It shoots a lot higher than I am used to so give me some slack on my posted target below. Once I got warmed up it turned in a nice group.

Member, glowe, turned me on to triple 7 for a BP substitute and I will say that I am more than happy with its performance.
The triple 7 provided PLENTY of smoke and, as such, it had a few people inquiring as to just what it was I was shooting. I felt that it cleaned up easier than Pyrodex.

One more point of interest.
The bore on this gun is deplorable, pitted throughout with one especially large area toward the end of the barrel, which always cast doubt on potential downrange performance. I guess this has me even more impressed with this old top break as it shoots as if the bore is fine.


35 Rounds fired off hand at 30 feet.
Ignore the holes at the corners of my target as they were from my 629.