Retired Army Col. Rene R. Studler, 85, an expert on small arms and a former executive vice president of the Washington International Horse Show, died of cancer Wednesday at Sibley Memorial Hospital.

Col. Studler, who had lived in Washington since 1940, was born in Blutton, Ohio. He earned a bachelor's degree at Ohio State University and a master's degree in engineering from the Massachusetts Institute of Technology.

During World War I, he joined the Royal Canadian Air Force. When the United States entered that war, he transferred to the U.S. Army flying corps and became of flying instructor.

Later in his career, Col. Studler worked primarily on the development and production of weapons and ammunition.

From 1936 to 1940, he was an assistant military attache in Britian. He also was accredited to Germany and France during those years.

In 1940, he was assigned to the War Department in Washington to work on the design of aircraft turrets. He became chief of research and development on small arms in the War Department and then in the Department of the Army and held that post at the time of his retirement in 1953.

After leaving the service, he was a consultant to the Army and Air Force on weapons development. He also was a consultant to a number of industries engaged in defense work. He retired a second time about 1978.

A devoted horseman, Col. Studler served as executive vice president of the Washington International Horse Show in the 1960s. He also was a president of the Washington Bridle Trails Association.

He leaves no immediate survivors.

Friends suggests that expressions of sympathy be in the form of contributions to the American Cancer Society.