Once it's moving on its own it operates as expected, but if you didn't know it was on Super you'd probably think it was on Standard Safety if you didn't know to just keep adding pressure. I'm thinking maybe just not enough metal taken off the sanded down trigger bits?
Trigger pull on SS very heavy
That is usually it. But, it could be that the lever is too loose, resulting in the cam not being rotated quite far enough forward to fully unlock.
6 days later
Definitely looks like my problem after cleaning out all the gunk and carefully watching it all move. I printed a negative of the cut-corner from the sample trigger in 4.4 as a gauge, and then gave up on sandpaper and put it on the grinder. Sadly it's going to rain tomorrow. If heavy rain, then sorry real guns, it's gonna be CoD BO6 open beta weekend 
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