Converting SA/DA to DAO

AR-10

New member
What is involved in converting a Smith model 60 from SA/DA to Double Action Only?

The obvious part of the conversion is to replace the hammer or grind off the hammer spur. I get the impression there is some alteration to the internals. If so, what exactly is involved?
 
You can grind off the hammer spur and make the gun less prone to snag clothing during the draw. Some revolvers even come that way from the factory. But they can still be fired SA by using the trigger to start the hammer back and catching the now exposed hammer with your thumb and then cocking it.

To actually convert to DAO does require internal modifications. If you were modifying a gun for your own use, I have never understood why you would want to do anything past taking the spur off the hammer.
 
Well..

Have to agree with the previous response but it did not answer your ?? so here ya go. Pop the side plate on the weapon, pull the 3 screws and then tap the grip frame with a piece of wood or lead to loosen the plate. Don't pry the plate off. Remove the hammer block safety. Now make sure that everything is is firm in the frame and then pull the hammer back slowly so you can see the action work (ya have to either put the cylinder back in to do this or pull the cylinder lock back) Now, when ya get the hammer back and it locks in the single action mode ya can see where the hammer locks on the sear. You need to remove that notch from the hammer. Lower the hammer (don't just snap it or ya will have parts all over the place) Remove the main spring. The flat spring is simple, remove the strain screw in the butt and then wiggle the thing out. On the J frames they have a different set up, ya have to pull the hammer back again and when the spring is compressed you will see a small hole in the strut. Place a small piece of wire in the hole, a paper clip works well. Lower the hammer and it will hold the spring. Then ya remove the spring and strut together. Pull the hammer back slowly until it clears the frame and then pull it out. Using a medium stone you then carefully remove the metal to take the single action notch out. When it's about gone switch to a fine stone and make it SMOOTH. Keep the angle the same as it was when ya do this. Re-assemble in the reverse order. Keep in mind that I am typing this with out a weapon in front of me but I think that covers it. Good luck.
Mike
Just reread your post and see that it's a J frame so ya can ignore the part about the flat main spring.
Mike
 
Thanks to both of you for the informed responses.

Mike's detailed instructions were pretty clear. The observation griz made regarding why anyone would go further than remove the spur sort of pinpoints where my inquiry originated.

Is there some advantage regarding lightening or smoothing the trigger that altering the internals would yield? I'm not asking about a trigger job, but rather some process that is part of making a revolver DAO involving more than lopping off the hammer spur. Does removing the sear engagement(?) on the hammer alter the feel of the trigger? Is it removed for reliability?

Thanks for the trouble you went to in answering my ????s. I do believe I will either get a modified hammer or a duplicate for my M60 that I can alter. Just wondering if there was anything else I need to change to keep it reliable.
 
Removing the SA cocking notch on the hammer doesn't alter the DA pull at all. It simply makes it unable to be fired in SA mode. One good thing about the MIM hammer is that after a bob-job, it's much easier to cock if you did want to shoot it SA. You carefully start the hammer to the rear with the DA trigger, then reach up with your thumb to grasp it in front of the hammer face. Obviously, this can be a tricky thing to do so use due care.:D

One last thing on bobbing J-frame hammers. Do not go for that smooth, 'fastback' look like you can get on a larger frame. You'd remove so much meat from the hammer that you risk a FTF. Just take enough of the spur off to make it less of a 'hook' in its ability to grap your clothing.
 
I'd suggest sending the revolver to a good gunsmith for a general action job, specifying a DAO conversion job as part of the package. I've done this several times with S&W and Ruger revolvers, using Clark Custom Guns in Princeton, LA (http://www.clarkcustomguns.com/ - IMHO, they do about the best trigger job of any of the "major" gunsmiths, in both "service" and "target" forms, although for individual perfection, Teddy Jacobsen of Sugarland, TX [http://www.actionsbyt.com/] is in a class of his own). You can also specify the strength of hammer strike that you need, depending on your carry ammo. - the gunsmith can replace springs as needed to adjust the hammer strike, even if the hammer is lightened by removing the hammer spur.

I've had mixed feelings about the removal of the spur. On the one hand, it's basically there to aid in cocking the weapon, so if you do a DAO conversion, it's irrelevant. On the other hand, it does aid in hammer weight, for a heavier strike: and if your holster has a safety strap, this is usually designed to fit over the hammer spur, so removing it makes that holster useless (or, at least, it won't properly retain the revolver with the safety strap any more). I've got DAO revolvers with and without hammer spurs, and I still haven't decided which I prefer. (Of course, if you remove the spur, this is an immediate visual indication that the revolver is DAO! I've forgetfully tried to cock a DAO revolver (with a standard hammer spur) once or twice, and one does feel an absolute twit when the hammer simply falls to rest again! Might be unsafe in an older gun without a transfer bar ignition system...)
 
Maybe I am just not real clever tonight, but it seems to me that the easiest way to convert a revolver to DAO is to just shoot it DAO. They don't, as far as I know, cock themselves, so if you don't thumb cock the gun, it is automatically DAO. And no gunsmith bill!

If you want to bob the hammer, too, that is OK but not part of making the gun shoot DAO.

Jim
 
Good point Jim.:)

Thing is, I was reading a thread here recently and someone mentioned that they had a snubby converted to DAO. It sounded to me like it involved more than removing the spur, so I thought I would ask.

I carry my M60 in my front jeans pocket from time to time, and the hammer spur is a problem. I think I will order a spare hammer from Brownells and bobbit. :eek: Then if I don't like it I can reinstall the original hammer and carry the Taurus concealed hammer jobbie I am trying to find new grips for.
 
here's a blast from the past...

back when we all carried wheelguns, some folks like to take "full advantage" of converting their guns to DAO. besides bobbing the hammer and removing the SA sear(on the hammer), they would "round off" the DA sear engagement surfaces so that the hammer would "roll off"...this was before the advent of the "roller action" modification.

and then there is the debate about if the lighter hammer requires a heavier spring (due to less hammer mass) or a lighter spring (faster hammer speed of lighter hammer)
 
I converted a S&W M58 to DA only a number of years ago. The reason is because I wanted to remove the hammer spur and I would never leave a spurless gun with SA capabilities. Tell me all you want about how it can be cocked by starting it back and catching it, it is still an AD waiting to happen. Also, what do you do if you decide not to shoot? Much harder to lower it safely. If the spur is gone, so should the SA notch.

I did this to make the gun more compact and "slicker" coming out from under a jacket. This is my walking around the woods gun and I will likely be wearing a coat and I want a smooth draw if I need the gun out. A combat revolver would seldom be used in SA anyway, so I don't think I have given much up in exchange for snag-free carrying.

A gun with adjustable sights doesn't gain much from this operation.
 
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