New parts for the Kimber

I finally got the stuff together to replace the fire control group in the Kimber.  I figured it would be a good idea to get all the parts from the same manufacturer to have the best chance of them working together without a lot of extra fitting on my end.  I chose STI, as they seem to make quality parts at pretty reasonable prices.  Plus the hammer I got looks pretty cool.  I had my Ed Brown sear jig out, but it turned out I didn't have to use it.  The STI parts mated together extremely well, even though they weren't sold as a pre-fit kit.  I did use my digital calipers and a feeler gauge to verify that the parts were dimensionally correct, and also checked the parts against the specs in the Kuhnhousen volume 1.  Everything looked good.

I was concerned that I would have to replace the thumb safety, but after switching out the hammer, sear, and disconnector I saw that the existing safety only needed to be filed a bit to fit with the new parts.  Sweet.  

The key to fitting a thumb safety is to go slow and test fit often.  Work with the gun put together, but without the grip safety so you can see what's happening when you test fit.  And don't get in a rush - a few strokes of the file and test fit, a few strokes and test fit.  If you lose patience and try to skip a few test fittings it's almost guaranteed you'll remove too much metal and have to buy a new part.  It's also helpful to have a properly fitted thumb safety nearby for comparison.  Of course every safety will fit differently, but you can compare the safety you're fitting with the other to see if you're filing the correct area with the proper angle, etc.  

Using the frame for a jig to check sear/hammer engagement isn't perfect, but you can kind of manipulate it to show you what you need to see.  These are the old Kimber parts.  Note the MIM marks on the hammer.  

These are the STI parts.  The new trigger pull is a consistent 4.75 lbs.  It's a little high, but I think it will come down a bit over time.  It's also a big improvement over the previous weight, plus it now breaks with zero creep, which is what I was most concerned about.  I need to test fire to make sure the new disconnector is working properly, but overall I'm happy with the way it turned out.  These parts are "in the white" so I need to get some cold blue or something to with which to finish them.  In the meantime I'm sure they'll be ok in the case with a coat of oil.