How about this great image of a U.S. Coast Guardsman in winter blues on an unidentified cutter alongside a stern 6-pounder 57mm deck gun circa 1916-1920s. Note the Portland Shipbuilding Company Spar Yard sign in the background, an outfit in Portland, Oregon that operated along the west bank of the Willamette River for 70 years.
USCG Historian’s Office 220211-G-G0000-032
The humble 6-pounder, of which the Navy had over 700 examples (of 13 types) on hand in 1901, was a common anti-torpedo boat gun designed in the 1880s originally by Hotchkiss then surpassed by competing designs by Driggs-Schroeder and Nordenfeldt.
They were a ready standby of the Spanish-American War era.
USS Newark. Electrician 1/c Sullivan with one of the ship’s six-pounder guns, in 1898. NH 80783
It was rapidly replaced during and immediately after the Great War in U.S. Navy service on all but local patrol craft, minesweepers, and auxiliaries with something larger or more effective — typically 3″/23s or 3″50s– although some models with decent elevation attributes were retained for a while as “balloon busters” and for use as saluting guns.
Nonetheless, the little gun endured with the Coast Guard.
A simple and light mount, typically less than 900 pounds without its shield installed, it did not penetrate the deck and required no electricity or hoists to move it or its handy 6-pound shells. Still, capable of being fired at rates of up to 20 shells per minute if the crew was well-drilled and, with a range of 8,700 yards, it could still bark.
Revenue Cutter 6-pounder drill with a four-man crew supervised by an officer, note the 6-pound shell at the ready, the flat caps, and the rarely seen USRSC officer’s sword. 210210-G-G0000-1002
For a service that, in peacetime, only needed a popgun to fire shots across the bow of smugglers and poachers and to poke holes in floating derelicts that posed a hazard to navigation, the QF 6 remained a viable option, appearing on several cutters well into the start of WWII and cutters so equipped practiced against moving targets (at a range of 750 yards) at least twice a year.
US Navy 6 pdr Service (left) and Target (right) ammunition via USN 1943 OP-4 Ord Manual
6-pounder and 3-pounder line throwing projectiles, via OP 4 (1943)
A reoccurring theme
Similarly, the Coast Guard continued to use the old WWII-era 5″/38 and 3″/50 guns, only retiring them in the late 1990s long after the Navy was done with them.
Last USCG 5 inch 38 being cut at RTC Yorktown 1993 or 1994
Last USCG 5 inch 38 being cut RTC Yorktown 1993 or 1994
Today the USCG is the final American user of the OTO Melera MK 75 76mm gun in U.S. service and has been since 2015.
That mount is likely to be retired in US service sometime in the 2030s when the final 270-foot Bear class cutters are put to pasture after 50 years of service.
The crew of Coast Guard Cutter Northland conducts a live firing of the MK 75 76mm weapons system while underway, on September 20, 2020, in the Atlantic Ocean. The cutter returned to its homeport of Portsmouth, Virginia, Wednesday after a 47-day patrol conducting counter-drug and migrant interdiction operations in the Caribbean Sea and Atlantic Ocean. (U.S. Coast Guard courtesy photo)
One day, they will probably be the last user of the Bofors 57mm MK 110.