Green’s Dictionary of Slang

1. (Aus.) a pack of lies [a load of bull n.⁶ (1)].

1962		H. Livings Nil Carborundum (1963) Act I: Three bags full.
1972		B. Rodgers Queens’ Vernacular 196: three bags full (late ‘60s) that’s a lie; bullshit!
1983		A. Payne ‘Willesden Suite’ Minder [TV script] 37: Three bags full, Mrs Bates.
2002		Pete’s Aussie Sl. Home Page 🌐 three bags full: a lot of bull, a pack of lies.

2. (Aus., also three-bagger) an act of masturbation [pull v. (8)].

1990		Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Three bags full. Masturbation.
1991		R.G. Barratt ‘I’m Pulling for Ya, Pee Wee’ in What Do You Reckon (1997) [ebook] Do you mean to tell me [...] I can’t have a three-bagger?
1999		R.G. Barrett Wind & Monkey (2013) [ebook] [H]e still had half a boner. Mr Wobbly was refusing to lay down. Christ! I’m half a mind to have a three bagger, he thought.

3. (N.Z. prison) an arrest, e.g. pull n. (3e)

2001

D. Looser Boobslang [U. Canterbury D.Phil. thesis] 188/2: three bags full n. a pull.