Ten galleons traveling from Havana to Spain went down off Florida's east coast, not far from Vero Beach, in the July 1715 storm. The vessel broke up and booty was flung far and wide.
"Over 350 gold coins including 9 Royals were recovered on July 30 & 31. This amazing recovery occurred on the actual 300th Anniversary" of the wreck, Brent Brisben, the head of 1715 Fleet - Queens Jewels, said on Facebook.
It was the second major find by the treasure hunters in recent months. In June, they found about 50 coins with a total of about $1 million.
The latest coins found are extremely rare and are worth about $300,000 each, Brisben said.
"These Royals are perfect specimens of coinage of the time and they were made on royal order for the king of Spain," he explained. And "we work extremely close to shore, which is surprising to most people," he said.
"These shipwrecks were pushed by the hurricane into the outer edge of the reef and then they were utterly destroyed by the wave action, so pieces of these ships have floated for miles all the way into the beach up into the dunes."
Under US state law, the state of Florida gets 20 percent of the returns on treasure found off its coasts.