Gun salute

In the United States, at noon on the day of presidential funerals, military installations across the country fire a 21 minute gun salute.

The system of odd-numbered rounds originated from Samuel Pepys, Secretary to the Navy in the Restoration, as a way of economising on the use of powder, the rule until that time having been that all guns had to be fired.

The Guns Platoon (as it is known for short) has the task of rendering military honors in the National Capital Region, including armed forces full-honors funerals; state funerals; presidential inaugurations; full-honors wreath ceremonies at the Tomb of the Unknowns in Arlington National Cemetery; state arrivals at the White House and Pentagon, and retirement ceremonies for general-grade officers in the Military District of Washington, which are normally conducted at Fort Myer.

The Presidential Salute Battery also participates in A Capitol Fourth, the Washington Independence Day celebration; the guns accompany the National Symphony Orchestra in performing the "1812 Overture".

The platoon maintains its battery of ten ceremonially-modified World War II-vintage M5 anti-tank guns at the Old Guard regimental motor pool.