you cant use tiger cannon because number 16 is a Katar type weapon... you can use this table as references. hope it helps you.
WEAPONTYPE_NONE = 0,
WEAPONTYPE_SHORTSWORD = 1,
WEAPONTYPE_SWORD = 2,
WEAPONTYPE_TWOHANDSWORD = 3,
WEAPONTYPE_SPEAR = 4,
WEAPONTYPE_TWOHANDSPEAR = 5,
WEAPONTYPE_AXE = 6,
WEAPONTYPE_TWOHANDAXE = 7,
WEAPONTYPE_MACE = 8,
WEAPONTYPE_TWOHANDMACE = 9,
WEAPONTYPE_ROD = 10,
WEAPONTYPE_BOW = 11,
WEAPONTYPE_KNUKLE = 12,
WEAPONTYPE_INSTRUMENT = 13,
WEAPONTYPE_WHIP = 14,
WEAPONTYPE_BOOK = 15,
WEAPONTYPE_CATARRH = 16,
in skill_require_db.txt i dont know what is the use of item type 99.,
EDIT:
sorry i was confused about your question... maybe you forgot some requirements to used it.