In the family table, whatever that column is that is giving that name, if you check the column properties, I bet it is set to "Member Display Name".
If not, then I believe the default naming structure is <Standard><Stock Number><unique> or something along those lines.
You can check what fields are being used by placing a default ANSI fastener and read what the browser name is placed. When you create custom is seems we have to force the member display name, but then it kills us if we have to place as custom because all these fields we "force" are then not overwritten by the "Custom" option. Which I get because it wouldn't know what to change. I just wish that custom would force the browser name to be file name at that point.
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