I recently purchased a 39-2 and after complete disassembly I have noticed that the hole in the bottom of the back strap insert which receives the main spring plunger is not a complete through hole but rather has a half moon shape to it so it is half a hole so to speak. The tit on the main spring plunger which holds the insert pin just partially protrudes through in the pin hole however it does seem to secure the pin. Is this the way it is designed or do I need to open the hole completely?
Thanks in advance for insight into this question.