The Civilian Marksmanship Program, a federally chartered nonprofit, has been selling surplus military firearms since 1996.

Between 2009 and 2017, the CMP brought in $323 million in revenue from those sales.

About 61% of that revenue came from selling the World War II-era M1 Garand rifle.

The Civilian Marksmanship Program is well known as the go-to place to buy surplus military firearms, so the Government Accountability Office recently tallied up how much money the nonprofit has generated from selling tens of thousands of M1 Garand rifles over the past decade.

Looking backward nine years from 2017, the GAO reports that the government-chartered CMP has brought in $323 million in revenue. About 61% of those earnings comes from selling M1 rifles, many of which were used in World War II and the Korean War.

"The primary source of CMP's revenues from fiscal years 2008 through 2017 was from the sale of surplus rifles, which, according to CMP's internal financial documents, generated $196.8 million in revenue," according to the GAO.

US Marine Corps Col. Randall Hoffman fires an M1 Garand rifle at Camp Perry in Ohio, July 31, 2018. Lance Cpl. Yamil Casarreal/US Marine Corps

The National Defense Authorization Act (NDAA) for fiscal 1996 authorized the CMP to sell certain types of surplus Army firearms to US citizens, including M1 .30 caliber rifles. The program reimburses the Army for the costs to prepare and transport surplus firearms to the CMP, according to the GAO report.

Since then, the Army has transferred more than 700,000 surplus firearms to the federally chartered corporation, which is also known for instructing US citizens in marksmanship and promoting firearms safety, according to the GAO report.

"The profit that CMP realized from the sales of surplus rifles could not be determined because CMP's methodology to calculate expenses did not account for all of CMP's costs associated with the sale of these rifles," it added.

US Army Maj. Gen. Clark Lemasters with an M1 Garand rifle at Camp Perry Joint Training Center in Ohio, July 9, 2018. Ohio National Guard/Sgt. Joanna Bradshaw

The CMP also began selling surplus M1911 .45-caliber pistols in November, so any revenue from that effort was not included in this GAO review, the report states. The NDAA for fiscal 2018 required the Army to transfer 8,000 to 10,000 surplus M1911 pistols for sale to the public during fiscal 2018 and 2019.

In addition to firearms, the CMP also sold commercial ammunition and memorabilia, which generated $76.4 million in revenue. According to its Internal Revenue Service filings for this time frame, the CMP reported earning $49.8 million in interest and dividends from its investment account, the GAO states.

The GAO estimates that surplus handgun and rifles currently available for sale could generate as much as $104.9 million, or "enough to fund CMP's operations for several years."

"Further, as of September 30, 2017, CMP reported having cash of $3.6 million, and an investment account valued at $188.6 million. This could also allow CMP to continue operations for several years," the GAO states.

— Matthew Cox can be reached at matthew.cox@military.com.