From a quick google search found these three records of horns blowing up. one recent and two historic. The Kansas one was fatal.
I forgot to write it down but I think this one was War of 1812. The accident occured on an American privateer.
"The first The battle lasted for nearly an hour. Tom Boyle brought up his marine detachment, commanded by Captain Robert Cascadden, and had them clear the enemy deck with musket fire. At 1:40 P.M. the badly damaged ship struck her colors. The Comet had two casualties; Thomas Cadle, a marine was hit in the eye by a musket ball, and William Cathell was badly wounded in the arm and leg when the powder horn exploded when he was priming his gun.
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The Hutchinson News
Hutchinson, Reno County, Kansas
Thursday, February 28, 1884
A young man, James Bertram, met with a horrible death last Friday, near his home in Little River township. He had been out hunting and the theory is his powder horn exploded, tearing out his bowels and setting fire to his clothes. He was discovered by the school children who saw the smoke. They then carried water in hats and extinguished it, finding young Bertram charred almost beyond recognition. He was buried on the following day.
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7/12/08
CHADRON, Neb. (AP) - A powderhorn exploded during Chadron's annual Fur Trade Days in Nebraska, sending a Denver man to the hospital with burns.
Authorities say the 35-year-old's injuries are not life threatening. The man's identity has not been released.
The explosion happened Friday at the buckskinner's camp southeast of town. The camp is one of the events featured