The heavily corroded explosives, thought to be from the Second World War, were discovered on Tuesday by farmer Allan Baird and his son Craig, 13, at Langholm Farm, near Symington, South Ayrshire.
Weeks of heavy rain on their field, which was being used by horses, had churned up the mud and brought the bombs to the surface.
“I was just walking through the field with my son when I noticed these pieces of metal sticking out of the boggy ground,” said Mr Baird, who owns the farm.
“I quickly realised what they were. It was a bit of a shock. I gently slid them back to the ground where they lay.”
“I phoned a friend, a policeman who used to be in the army, and it wasn’t too long before bomb disposal experts were here.”