To (prospectively) have penetrative sex with a female.
Possibly of Australian origin, this jocular euphemism for sexual intercourse is typically used by men discussing the attractiveness of a specific (but non-present)
woman.
The phrase may be a derivation of the derogatory
joke "She'
s so loose, it was like chucking a chipolata up the high street" in which the male speaker not only slanders the large size of the female subject's
vagina, but also disparages the size of his own penis.