View Full Version : Pinning a full cock notch.

August 19, 2010, 12:15 PM
I had mentioned in a previous thread that I was going to pin the full cock notches in my Pietta Hickok revolvers becuase the trigger pull, while smooth and light, was loooong. Junkman and others asked for a tutorial on how I do this. So here it is.
One caveat this does not lighten the pull so if you need to smooth or lighten the pull do it first. I boost the hammer and that for me works better than stoning but however you do it, do it first.
I got both revolvers down to 32OZ pulls very smooth but they went on forever. I like the breaking a glass rod feel.
The first pic shows the tools and material needed. The hammer is case hardened glass hard. You need a carbide drill to get through it. The one showen is 5/64 from a set I bought for ten bucks from Harbor Freight they are ground to an angle that does not require a center drill to start just go slow and it drills through the case like so much butter. I drill about two diameters deep. The pin material is 5/64 music wire. This just happens to be what I had 1/16 or 3/32 would work equally well as would mild steel or brass rod.
The second photo shows getting ready to drill I stay just far enough in front of the full cock notch that I won't be drilling into the hole for the hand.
Once the hole is drilled I chuck the music wire in an electric drill and put a light bevel on the end. Since these drills are precision and drill an exact hole the music wire is a slip fit. You can hold it in place with red locktite or do as I do and lay the end on an anvil and bump it up a thousandth or so and drive it into place. I cut off most of the excess with a wheel in a dremel tool. I then file it with a slim pillar file until it looks about right and test fit it on my jig. You want about half or a little less of what had been full engagement.
The last photo shows checking that clearing the full cock notch will also clear the half cock. Pietta gets their hammer geometry right and it will clear with no problem. Some ASM and others it may not and you will have to round the tip of the half cock and it is better to check now than have the tip of your sear bang into the half cock.
Some folks put down a thin layer of JB Weld and dress it down when cured and that also works.
The results are that I now have two revolvers that have 32OZ stable break like glass trigger pulls.
Now all I have to do is get to the range again.

August 19, 2010, 12:17 PM
Last two photos.

August 19, 2010, 01:57 PM
EXCELLCENT !!!!! Just peachy. An old dog like me can learn new things.
This is the very best way I have ever heard of. I would go one step further
and tap the hole say 8/32 or so and put a little allen screw in so you could
actually adjust the trigger pull. We like ours under a lb. around 6 oz. or so.
Just a excellcent idea!

August 19, 2010, 02:35 PM
kwhi43. No reason why you couldn't put in a set screw to adjust length of pull. As to weight of pull you would need to go with a lighter trigger/bolt spring maybe one of the music wire ones. Although with the shorter pull this feels a lot lighter than 32OZ but trigger pull guages don't lie.

August 19, 2010, 02:37 PM
One other thing 8/32 might be a little large. I'd probably go with a 4/40 or at most 6/40.

August 19, 2010, 03:39 PM
Good Thread!!!! I have a Black Hawk that has a three inch trigger pull. (well maybe not that long) I'll do this for my next gunsmith project.
The thing that is attractive to me is that a mistake is rectified by pulling the pin and going back to the original.

August 19, 2010, 03:53 PM
Nice job!
A much cleaner modification than using the JB goo.