Fitting A Caspian Grip Safety To A Double-Stack Kimber
-- Shannon Jennings; Coal Creek Armory, Knoxville, TN
Good as new: Shannon’s customer’s Kimber BP Ten fitted with a Caspian grip safety.
A customer brought into our shop a Kimber Pro BP Ten that would not fire. The BP Ten is a double-stack, polymer framed 1911-type that was never very common and has been out of production for 5 years or so now. The problem was a broken plastic grip safety. On Kimbers, depressing the grip safety pushes up the push rod that operates the firing pin block (firing pin safety). We called Kimber, but they did not have any replacement grip safeties. I wondered if a Caspian wide body grip safety could be modified to fit the Kimber. When I talked to the folks at Caspian, they didn’t know, but I ordered the Caspian grip safety anyway(#168-000-053. The short answer is, yes it can be fit. It requires reducing the frame's grip safety radius to .220". Here’s how I did it…
First, strip the frame. Then file down the grip safety radius using the Smith &Alexander jig (#849-009-000. The sides of the grip safety below the arms need to be narrowed .040" per side. This will almost completely go through the left sidewall of the safety. Just break out the thin web left.
At this time, remove little or no material from the bottom of the arms. I did this with the milling machine and a long 1/4" end mill (see photos 1 and 2). Be sure to have a firm hold on the grip safety in the vise. Be careful to not cut farther toward the rear of the grip safety than necessary or you will hit the wider portion of the safety. You will need to remove .015" from the tops of the arms initially. Do not narrow the safety above the arms. You may need to file or mill a little material from the top and bottom of the arms until you get the grip safety in the pistol.
Once the grip safety is installed, photo 3, install the parts back into the frame, photo 4. File or mill the bottom of the grip safety's arms until the push rod can retract flush with the top of the frame. Remove material from the top of the arms until the grip safety can be fully depressed.
At this point, I thought it was a decent fit, but I went ahead and blended the grip safety to the frame. Blending did require removing a fair amount of material from the grip safety. I touched up the frame and finished the safety with Graphite Black oven-cure Cerakote (#100-003-743. The Cerakote was baked at a gentle 200 degrees for 2 hours so the plastic part of the frame would not be harmed by the heat.
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