WAIKĪKĪ — By 1914, the two big guns at Fort DeRussy's Battery Randolph at what is now the U.S. Army Museum of Hawai'i could hurl 1,556-pound shells 12 miles out to sea.

Their installation followed a time when the British, French, Russians, Germans and Japanese all had ships in the Pacific — and interest in Hawai'i.

The twin, 14-inch guns were the largest in the Pacific from California to the Philippines, according to the museum. Battery Randolph also had reinforced concrete parapets, or walls — behind which the guns were placed.

"If we were shooting at an enemy ship, we expected them to shoot back, so we were well protected," said museum curator Dorian Travers.

The parapets were razed in 1969 along with an adjacent gun emplacement called Battery Dudley.

Under a $725,000 project, the Battery Randolph barricades are returning, but with a dual purpose: recreating a bit of history and a lot of additional museum space.

Rather than use solid concrete, the Army is rebuilding the parapets with a stucco-type exterior and enough room inside for offices, an education center and other uses, officials said.

"The interior of the replica gun parapets will create an additional 7,400 square feet of desperately needed space to collect, preserve, interpret and display the U.S. Army's collection of historical property," said museum director Judith Bowman.

U.S. Army Reserve soldiers with the 980th Engineer Battalion headquartered in Texas are using the 63-day project as their annual training mission by rotating through Hawai'i three sets of engineering companies.

"This is a great training opportunity regardless of where it's located," said Maj. Rusty Rhoads, the battalion's operations officer. "The fact that it's on Waikīkī Beach is a bonus."

The Reserve soldiers started work on May 8 and the exterior is expected to be finished on the up to 22-foot-wide rooms by about July 6. The museum, which draws about 100,000 visitors a year, has remained open during the construction.

About $250,000 of the total cost is coming from membership and donations made through the Hawai'i Army Museum Society, a nonprofit organization that supports the museum, said Executive Director Vicki Olson.

Olson said the largest contribution was made by local philanthropist Dr. Lawrence K.W. Tseu. The remainder of the funding was obtained from the U.S. Army Center of Military History, she said.

According to the museum, Battery Randolph's big guns were designed with "disappearing" carriages that, when fired, rocked backward and locked in place behind the safety of the parapet.

When the guns were scheduled to be practice fired, advance notice was run in the newspaper advising anyone within a half mile's distance of the battery to open their windows and doors and secure loose objects.

By 1946, Battery Randolph had outlived its usefulness and the 14-inch guns and their carriages were dismantled and sold for scrap. Two 7-inch naval guns are now installed on the "gun deck."

In 1969, batteries Dudley and Randolph were scheduled for demolition to make way for the Hale Koa Hotel. A contractor semi-successfully demolished Battery Dudley, which had two 6-inch guns, and the parapets on Randolph, but the rest of the reinforced concrete turned out to be too much of a challenge.

"They went bankrupt. Legend has it that the wrecking ball broke first," Travers said.

The conversion of Battery Randolph into an Army museum began in the mid-1970s.