Chip McCormick grip safety installation

[sutureman]

I just ordered a Chip McCormick beavertail grip safety and was wondering how hard it is to install. I have an AMT frame with a Colt Model 70 slide. Does anyone have any experience with this safety and did it "drop-in" or need frame modifications (i.e., filing)?

[brickeyee]

At the very least a grip safety requires adjustment of the 'hand' length to correctly block the trigger.
You get to decide if you want to grind the frame to more closely match the safety.

[Jon]

when I installed the Chip McCormick grip safety and bobbed hammer, I didn't have to do any modifications to either the safety or the gun. Of course, I now have a weird issue with the thumb safety disengaging when I pull back on the hammer, so maybe I should have done some filing and grinding somewhere. (going to contact McCormick again today about this issue).

[brickeyee]

"Of course, I now have a weird issue with the thumb safety disengaging when I pull back on the hammer"

That would likely be caused by the fact that it is not correctly fitted. The tolerance stackup for the grip safety requires they not be as simple as a 'drop in'.
The same problem occurs with thumb safeties. At some point the tolerances must be removed to ensire correct functioing of these safeties. Hand fitting of the part on the actual frame and tothe other components used is how you ensure the safeties work correectly.

[7790314]

Buy or make a fitting jig. This site contains all of the information you will ever need to know about fitting a grip Safety with a .250 radius. http://www.homegunsmith.com/ It ain't hard. But there is more to it than just fitting the dog that blocks the trigger. Also at roderus custom the resident guru used to have his own web page with all kinds of 1911 gunsmithing information too. Also this guy gives a pretty good description on fitting a .250 radius grip safety. http://www.blindhogg.com/