About 1,000 people attended the event at Twyford Wood near Bourne in Lincolnshire on 23 May.
Police carried out an operation to close down the event which led to 21 officers and a police dog suffering injuries.
Lincolnshire Police said the level of violence directed at officers was "totally unacceptable".
One officer was hit by a car, while a police dog was struck by a glass bottle.
Most of the defendants, who are from various locations across the UK including South Wales, Wiltshire, Norfolk and Bristol, were charged with violent disorder.
Those admitting violent disorder at Lincoln Crown Court on Thursday were:
Owens also admitted two charges of supplying drugs, a further charge of possession of cannabis with intent to supply and also illegal possession of ketamine.
Fabian Gibertoni, 19, of Sheffield, and Kirsty Wiggins, 24, of Cirencester admitted possession of ketamine with intent to supply.
They will all be sentenced in July along with three other men who admitted violent disorder at an earlier hearing.
They are Oliver Rickman-Williams, 23, of Stroud, Gloucestershire, Michael Carden, 22, of Brimscombe, Gloucestershire and Kieran Wilson, 23, of Hoveton, Norfolk.
Three other defendants face trial after denying charges.
Alan Brown ,31, of Bury St Edmunds, Suffolk, denied an offence of public nuisance by providing a generator for use at the rave.
Jonathan Lawson, 25, of Norwich, denied two charges of possession of drugs with intent to supply.
Stephen Kelly, 26, of Bristol, denied possession of MDMA with intent to supply.
Eighteen people charged with violent disorder at an illegal rave in Lincolnshire have pleaded guilty.