That should about cover it

In my last post I mentioned the top cover of the Uzi.  Like many of the other parts, it needs to be modified for semi-auto use too.  It's got this nifty ratchet mechanism on the charging handle to hold the bolt open.  An added safety precaution on an open bolt machine gun, and just a handy feature to have on a closed bolt semi-auto.  The problem is that the semi bolt doesn't move back as far as the FA bolt, so the original charging handle ratchet can't go back far enough to unlock and slide back forwards.  The ratchet unlocking mechanism is super simple, and activates when the spring inside hits the back of the slot.  A lot of people simply take the ratchet mechanism out for their conversions, but I like it.  All that's needed to modify it for semi-auto use is to make the slot shorter to match the shorter travel of the bolt.  Conveniently, the top cover sheetmetal is the same thickness as the receiver, so I cut a leftover piece of receiver to fit the slot.  For my conversion, I needed to add a piece .825" long.  Your results may vary, but it should be around there someplace.