In October 1971, a rifle made during the Revolutionary War was stolen from a display case at the visitor center at Valley Forge State Park in Pennsylvania.
The case was thought to be theft-proof, but someone used a crowbar to pry it open in broad daylight, soon after the museum, about 20 miles northwest of Philadelphia, opened that morning, according to The Philadelphia Inquirer, which wrote about the theft at the time.
Some time later, a boy scout on a tour with his troop noticed that the rifle, a five-foot-long weapon made by a master gunsmith, Johann Christian Oerter, was missing.
Forty-seven years later, in July 2018, the man who stole the rifle, Thomas Gavin, sold it, along with a trunk filled with more than 20 antique pistols and a Native American concho silver belt, to Kelly Kinzle, a Pennsylvania antiques dealer, who paid him $27,150, according to federal court documents.
On Tuesday, Mr. Gavin, 78, pleaded guilty to one count of disposing of an object of cultural heritage stolen from a museum, a charge that carries a maximum penalty of 10 years in prison. He was ordered to be held with bail set at $100,000 before he is sentenced on Nov. 15.
His lawyer did not immediately respond to a message for comment.
In February 2020, F.B.I. agents and detectives from the Upper Merion Township Police Department questioned Mr. Gavin, who admitted that he stole the Oerter rifle as well as antique guns from other museums across Pennsylvania, according to a plea agreement.
Mr. Gavin admitted that he stole revolvers and pistols from several institutions, including the American Swedish Historical Museum, the Valley Forge Historical Society and the Pennsylvania Farm Museum, the plea agreement said. The weapons, one of which had a bayonet, were made in the 18th and 19th centuries, the document said.
He also confessed to stealing the silver belt and several firearms made in the 1850s from the Hershey Museum in Hershey, Pa., according to court documents.
The rifle that was taken from the Valley Forge visitor center was made in 1775 by Oerter, a gunsmith at the Moravian settlement of Christian’s Spring, near Nazareth, Pa.
David Condon, an expert in antique firearms who examined the rifle, said its market value was $175,000, according to court documents.
A lawyer for Mr. Kinzle, the antiques dealer, told The New York Times in 2019 that his client discovered that he had bought a stolen weapon after he read about the theft of the Oerter rifle in a 1980 book by George Shumway, an expert on antique long rifles who died in 2011.
The rifle was among a number of antique firearms that were stolen from the Valley Forge Historical Society and the Valley Forge State Park museum in the late 1960s and 1970s, according to federal prosecutors. Valley Forge was established as a national park in 1976.
Prosecutors said that Mr. Gavin should be ordered to pay no more than $20,200 in restitution, according to the plea agreement. They did not stipulate what sentence they would recommend to the judge.
Man Admits to 1971 Theft of Revolutionary War-Era Rifle is written by Maria Cramer for www.nytimes.com