One of the things I drag my feet on doing is the firing pin hole in the breech block. There is probably a better way to do it than the way I have been doing them, but so far this has worked for me.
Today was the day because I had to get it done in order to continue with other items on the list.
Picture 1 shows the layout lines and angle the firing pin runs in the block (red arrow). Now, if I was Greg, I would be figuring out a way to use a transfer bar and put the firing pin in straight. While I will experiment some, I don't really have the time on this gun.
At this point I had already found the center of the bore on the face of the breech block, I explained this earlier. Then, set in the mill vice, I lined up on the dimple and centered it under the mills spindle. I have the breech block laid flat at this point, and had already done this once before, but decided to change the setup so I had to redo it. Second picture.
Third, with the breech block setup for the firing pin angle I again centered the dimple under the center of the mill spindle. I really only needed to do one directed, x I believe real machinist call it, since the width (y) does not change in relation to the vice fixed jaw.
Fourth picture, here you can see both the breech block, centering tool and my DRO. The DRO is set at zero.
Last picture, You can see the DRO is now set to .025. Since this firing pin sets at about a 24 degree angle, the firing pin hole is lowered .025 to compensate for the pin movement at this angle so that it still hits the approximate center of the primer anvil.
I will add that at this point that I have not made the final breech block link. But, this temporary one has the exact spacing I intent to use on the final link. But, if the firing pin is off up or down I can still correct it with different link hole spacing.
More in the next post.
Bob