I managed to gem in Bombadier and AuS with an Attack +7 --- charm, and gem out Stamina. You can probably get AuM and gem out stamina with an Attack +5 charm. You can also gem in CE+3 with an Expert +10 charm, which at least one type should exist in each table that's not cursed, with two more spots to gem out stamina.
Really though, it depends on what weapon you use. What weapon do you use?