LAS VEGAS -- The U.S. Army on Thursday awarded Sig Sauer a contract worth $580 million to make the next service pistol based on the company's P320 handgun.

Sig Sauer beat out Glock Inc., FN America and Beretta USA, the maker of the current M9 9mm service pistol, in the competition for the Modular Handgun System, or MHS, program.

"We are both humbled and proud that the P320 was selected by the U.S. Army as its weapon of choice," Ron Cohen, chief executive officer of Sig Sauer, said in a statement to Military.com here at SHOT Show, the world's largest gun show, taking place this week in the city.

"Securing this contract is a testimony to Sig Sauer employees, their commitment to innovation, quality and manufacturing the most reliable firearms in the world," Cohen added.

The 10-year agreement calls for Sig to supply the Army with full-size and compact versions of the gun. The pistols can be outfitted with silencers and accommodate standard and extended capacity magazines. The firearms will be manufactured at the company's facilities in New Hampshire.

The Army launched its long-awaited XM17 MHS competition in late August 2015 to replace its Cold War-era M9 9mm pistol.

"By maximizing full and open competition across our industry partners, we have optimized private sector advancements in handguns, ammunition and magazines, and the end result will ensure a decidedly superior weapon system for our warfighters," Army Acquisition Executive Steffanie Easter said said in a press release.

One of the major goals of the effort was to adopt a pistol chambered for a more potent round than the current 9mm. The U.S. military replaced the .45 caliber 1911 pistol with the M9 in 1985 and began using the 9mm NATO round at that time.

In their statements, Army and Sig officials didn't specify what caliber the new Sig Sauer pistol will be.

Sig touts the P320 model product as "modular" and "adaptable," with interchangeable grips, multiple sizes and calibers that can be converted between 9mm, .357SIG and .40S&W. "From calibers, to pistol size, to the grip fit best suited for the shooter, the P320 is the most adaptable pistol available today," the company says in promotional materials.

Two sources confirmed to Military.com that Sig submitted to the Army .40-caliber and 9mm pistols for consideration. One source said the Army ultimately selected the 9mm version.

Shortly after the contract announcement, Sig officials celebrated here at the show. Staff at the Sig Sauer booth set out champagne flutes for a celebratory toast.

The Army in December down-selected to two finalists for the competition: Sig and Glock, which had submitted its Glock 17 and Glock 19 models for consideration. Given the size of the contract, Glock is widely expected to protest the decision.

Brandie Collins, communications manager for Glock, said she had not been briefed on the contract award but wished the winners well.

Army officials informed Beretta USA and FN America at the show that they had been dropped from the competition in the recent down-select decision, according to a service source who is not authorized to speak to the press. But confusion reigned as reporters informed company officials of the Army's announcement.

The decision formally ends the Beretta's 30-year hold on the Army's sidearm market.

Gabrielle de Plano, vice president of Beretta Defense Technologies marketing and operations, said staff were still reading through the contract announcement to fully understand it.

"It's going to have to be a no comment from us for now," he said.

Beretta has fought hard to remain to remain the Army's pistol maker. In December 2014, Beretta USA submitted its modernized M9A3 as a possible alternative to the Army's Modular Handgun System program.

But the Army rejected the improved M9A3, which featured new sights, a rail for mounting lights and accessories, better ergonomics and improved reliability. The company, however, wasn't finished yet. It developed a new striker-fired pistol, the APX, and entered it into the competition.

Kristina DeMilt, public relations for FN, said officials at the show hadn't been informed of the award and were not immediately prepared to comment.

The Army began working with the small arms industry on Modular Handgun System in early 2013, but the joint effort has been in the works for more than five years. It could result in the Defense Department buying nearly 500,000 new pistols.

Current plans call for the Army to purchase more than 280,000 handguns, according to Program Executive Office Soldier officials. The Army also plans to buy approximately 7,000 sub-compact versions of the handgun.

The other military services participating in the program may order an additional 212,000 systems above the Army quantity.

"As MHS moves forward into operational testing, the due diligence taken by all of the stakeholders will ensure a program that remains on-budget and on-schedule," Easter said.

Lawmakers may be eager to hear such an assessment.

During last week's confirmation hearing for retired Marine Gen. James Mattis to become defense secretary in the Trump administration, Republican Sens. Joni Ernst of Iowa and Thom Tillis of North Carolina took turns criticizing what they described as an overly bureaucratic effort, with technical requirements totaling several hundred pages.

-- Brendan McGarry contributed to this report.

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

-- Hope Hodge Seck can be reached at hope.seck@military.com. Follow her on Twitter at @HopeSeck.