All,

Below are pics of how I altered the semi striker so that the rifle could not be fired "out of battery". These are pics of my rough prototypes to show how it works. The second pic shows the set up at the instant of firing. The length of the firing pin and tab offset have to be coordinated so that tab cannot hit the FP unless the carrier is in the full forward position. About 1/4" must be left clear to the rear of the tab so that the recoil buffer will work.

Joe