You may think about making a captive secondary sear shelf just before the firing pin start coming out of the breach face. This will ensure that if the pen is dropped in the uncocked position it can't go off, and it will also prevent the firing pin from touching the primer unless the trigger is held down.
It would also be possible to add a sliding safety to it.
Edited by TDK (01/06/15 05:39 PM)
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