Getting the trigger pin lined up just right.

[4ster]

I am building a Chambers Kentucky pistol. This is my second build from a kit so I am still very wet behind the ears.  In my previous gun the part of trigger that engages the sear was rectangular shaped.  Placement was done by placing the trigger in position on the cocked sear and drilling the pin hole as high and forward as possible.  I don't remember worrying too much about getting the pin in position on the stock, I measured the trigger and made a mark on the stock to drill. There was a reasonable amount of room for error since I was aiming for a spot on a rectangle.

I am getting near the point of installing the trigger and this Chambers trigger has me scratching my head.  To get the pivot point  high there is a little ear on the forward part of the trigger that the pin has to go through.  There is no room for error.  

The only thing I can think of is somehow clamping the trigger in my cross slide vice on my drill press so that it stays fixed and then moving the stock into position over the trigger.  There has got to be a better method I'm not thinking of.

[flehto]

I drill the hole at the centerline of the half circle on the trigger and then lightly clamp the trigger on the outside of the lock panel, align the forward edge of the trigger bar w/ the forward edge of the slot in the trigger plate, position the trigger in and out for a slight amount of clearance between the trigger plate and top of the  trigger shoe  and having marked the sear position on the wood, position the trigger for best leverage for a suitable trigger pull. Tighten the clamp and spot the pivot hole , remove the trigger and driill through. Of course a little backward angle for the trigger shoe looks better than forward. The slot in the trigger plate can be short and then lengthened after the trigger is pinned. Be aware that the pivot hole could break through at the edge of the sideplate inlet, if it's in. Good luck....Fred

[bob in the woods]

Measuring depth /position etc with my vernier,  I've done 4 Chambers kits, and haven't missed the proper
pin location yet      Measure twice/thrice...drill once !!

[D. Taylor Sapergia]

I use the same method as Fred.  Here's a few pics of the sequence on an old build of mine. 
First you need a plan.  If you can't draw it, you likely can't make it work on the wood, or at least, you'll be scratching your noodle a lot trying to figure it out.  In the first image, I have prepared both the trigger and its plate, and the guard ready for inletting.  I can see how the relationship of each piece is going to work.  The second image shows the slot being hacked out of the wood for the trigger.  In the third, like Fred, I clamp the trigger in it's position onto the lock panel, and drill vertically through the hole into the wood.  This way, it's difficult to get it wrong. 
This rifle used a Chambers' Large Siler lock, and with the simple trigger, I achieved a 2 pound trigger break.

[4ster]

Thank you gentlemen, your explanations are great.  As usual I was overcomplicating the problem.

[Bentflint]

Good pictures Taylor. I too like to get the trigger pinned betwine the sear screw and lever. Reduces the friction on the lever/trigger contact point.

Steve just remember the closer to the lever the trigger is pinned the lighter the pull but the longer the trigger creep.

Bruce

[4ster]

Trigger installed and working beautifully.  My last build was a military gun and has a uh, "military" trigger pull.  This one is very light and will be a great target trigger.  Since this is a precarve stock, geometry was pretty well determined with only  a little wiggle room for adjustment, but I'm happy with how it turned out.

[David R. Pennington]

My current build is an early southern style with a single trigger. I studied Peter Alexander's explanations on trigger geometry and basically did it like Sapergia says. I was real pleased with the results. After tuning the lock and putting it all together I have a trigger pull of only a few ounces.