Three Jamaicans arrested in Cayman last year following a drug bust entered guilty pleas in the Grand Court on Tuesday.
Assad Walker, Fitzroy Ottey and Owen Reid were seen throwing packages off a canoe in March 2018.
The police seized the packages which contained more than 300 pounds of ganja, 101 grams of cocaine, 49 grams of ecstasy, a handgun and 49 rounds of ammunition.
The Jamaicans said they were paid to transport the drugs from Jamaica to Cayman, and when they arrived at the departure location, the boat was already loaded.
While they suspected the packages contained ganja, they denied ever knowing the other items were included in the packages.
A sentencing hearing has been set for Thursday.