Derek McLennan and Gus Paterson used metal detectors to discover the coins in a field at Twynholm, near Kirkcudbright in Dumfries and Galloway.
The men discovered 322 coins, which are said to carry images of various monarchs of the time.
They will show them to local residents before handing them over to Scotland's Treasure Trove Unit. The unit aims to ensure significant or important finds are kept for the nation and go on show in museums.
Mr McLennan said they suspected the field would yield something interesting, but were on the verge of giving up when they first made the discovery.
He said: "We had done quite a lot of research and had targeted that particular area. We had searched several fields around it before we stumbled across it.
"We had been searching for probably about five hours in atrocious weather with rain and 60mph gales.
"We were both feeling rather scunnered in the last field before we headed for the car."
On the first day of looking they netted about 40 coins as darkness fell, but subsequent return trips to the site took the overall total to 322.
Mr McLennan said: "I went in one direction and Gus went in the other and Gus was lucky enough to hit the first two coins.
"There was jubilation all round as I'm sure you can imagine."
He said they quickly realised what they had discovered.
He added: "Although it's a hobby we are serious about it so we immediately recognised that it was medieval hammered coins. It was actually two stuck together, which is highly unusual, so that led us to believe there was a possible hoard of coins in the area and we just started searching."
In a discovery back in July last year, a Roman coin hoard was found at the site of the Belladrum music festival in the Highlands.
Some of the 36 denarii were discovered by Eric Soane using a metal detector during a clean up of discarded tent pegs after the 2012 Belladrum.
A dig led by archaeologist Dr Fraser Hunter uncovered the rest of what was the first Roman coin hoard to be discovered in the Beauly area.
The number of archaeological finds handed over to the Treasure Trove Unit more than doubled in the space of one year, it emerged in the summer.
There were 316 cases of historical items being handed over to the Treasure Trove Unit in 2012-13, up from 152 the previous year.
The finders were given payments ranging from £5 to £10,000 as a reward, depending on the value of the items.
These payments totalled £36,510 in 2012-13, with most of them being for a few hundred pounds.
As well as finds by members of the public, the annual report on Treasure Trove in Scotland revealed there were 194 cases where professional archaeologists handed over items unearthed on digs and excavations - with 134 of these resulting in artefacts being given to museums.
Some of the items that were found include a hoard of 219 Roman coins discovered in Ashkirk, in the Scottish Borders, which have been allocated to the Scottish Borders Museums Service.
In 2011, David Booth, chief ranger at Blair Drummond Safari Park, found four golden neck ornaments, or torcs, near Stirling, which had been in the ground for an estimated 2000 years.
He received a payment of £462,000 - the largest reward at the time.