Green’s Dictionary of Slang

(Aus.) razor gangs.

1931		Referee (Sydney) 4 Feb. 12/3: A razor slasher is merely a ‘Bengal lancer’ under another name.
1937		Northern Miner (Charters Towers, Qld) 22 Feb. 4/3: Suddenly Paddy’s sparring partner picked up a bottle, and [...] yelled at the Irishman, ‘I’m a bottle king you Irish cow, so keep quiet’ Paddy quickly grabbed his razor from a box. ‘Yeah,’ he exclaimed. ‘If you're a bottle king I’m a Bengal Lancer’.
1945		Baker Aus. Lang.