12 grains? Wow! You never mentioned what that charge weighs. I've heard they hold about 25 grns of 3F.
Someone messaged me with a really awesome fix job for the Pocket Colts, which was to place a thin bar across the recoil shield and to make a recess in the hammer nose for that wire. This way the safety pins can still be used and the wire holds the caps back from falling off of the nipples. But I cannot seem to find it anywhere. I'll keep checking for it though, as I've read many of the "fixes" aren't 100%.