A search by amateur archaeologists from the Conflicts of Interest group made the discovery at Sandaig on the north side of Loch nan Uamh in Lochaber.
It is understood that the ammunition landed by boat on April 30 1746, around a fortnight after the Jacobites lost at the Battle of Culloden, with the hoard distributed and hidden locally.
"For around 250 years there, a hoard had lain undisturbed by one particular croft," said Paul Macdonald, of Macdonald Armouries, who helped with the search.
The complete hoard included 215 musket balls and a number of gold and silver gilt buttons and coins , as well as some other non-ferrous items, Mr Macdonald added.
He said: “From what the finds tell us to date, the musket balls were cast for use, yet never fired and correspond with the same calibre of musket balls landed nearby with French arms for the Jacobite Rising by the ships Mars and Bellone on the 30th April 1746.
“The arms were of course landed a couple of weeks after the Battle of Culloden and never saw service, but were rapidly distributed and hidden locally.”
Mr Macdonald said the now-ruined croft where the musket balls were found was once inhabited by the famous Clanranald bard, Alasdair MacMhaighstir Alasdair, who was an Officer in the '45 Rising and served as Gaelic tutor to Prince Charles Edward Stuart.
He lived out his later years here at this croft until his death in 1770, Mr Macdonald added, with the group given permission to use their metal detectors on the land.
Loch Nan Uamh is where Bonnie Prince Charlie left Scotland for France after his defeat at Culloden, where the rising to restore the Stuart line to the British throne came to a end.
He departed Scotland for France on September 19 1746 after wandering the Highlands and Islands for five months as the authorities pursued him.
The find has been reported to Treasure Trove, which distributes items of significance to Scottish museums.