The Second Life of the Pentagon’s Magic Bullet
The US military's Hypervelocity Projectile is steadily inching towards combat.
For nearly two decades, the US Defense Department chased a tantalizing dream that never quite panned out: an electromagnetic railgun capable of firing projectiles at Mach 6 to obliterate incoming threats. But after spending nearly $1 billion on the much-hyped futuristic weapon, the US Navy shelved the program amid mounting financial and integration hurdles.
While the railgun itself was mothballed, the projectile it was designed to fire — an ultra-fast, ultra-dense slug — is quietly getting a second life across the US military.
Known as the Hypervelocity Projectile (HVP), defense prime BAE Systems describes the specialized round as a “next-generation, common, low-drag, guided projectile” for multiple missions ranging from naval gunfire support to cruise and ballistic missile defense. According to BAE’s spec sheet, the HVP weighs around 28 pounds and is capable of nailing targets at ranges of up to 100 nautical miles when fired from the railgun it was originally designed for. Variants of the HVP are also compatible with the Mk 45 5-inch deck guns installed aboard the Navy’s Arleigh Burke-class destroyers and Ticonderoga-class cruisers and the now-defunct Mk 51 Advanced Gun System (AGS) developed for the service’s Zumwalt-class destroyers, as well as the US Army’s 155 mm artillery systems.
These capabilities make the HVP especially appealing to a US military increasingly grappling with the persistent threat of low-cost weaponized drones and missiles. Its high-speed, low-drag profile gives it a short time-to-target, while its relatively small size allows for deep magazines and rapid salvos. And at an estimated unit procurement cost of around $85,000, it is a significantly cheaper alternative to legacy interceptors like the $2 million Standard Missile-2 the Navy has relied on heavily during Operation Prosperity Guardian, the ongoing Red Sea campaign against Iran-backed Houthi militias in Yemen.
Ironically, it was the HVP’s versatility that helped doom the railgun project. As I previously wrote for Laser Wars, the Pentagon’s secretive Strategic Capabilities Office (SCO) realized in 2015 that the projectile was just as effective against targets when fired from powder-based systems — specifically the Mk 45 deck guns that are ubiquitous across most Navy surface combatants. A subsequent 2016 Center for Strategic and Budgetary Assessments study indicated that those guns could fire off HVPs at Mach 3 at distances of up to 30 miles, more than twice the range and speed of their conventional 5-inch shells. Why wait for the Office of Naval Research (ONR) to perfect the ridiculously complex railgun and go through the trouble of integrating it into a warship when you can rapidly proliferate a relatively cheaper solution across the fleet?
“We thought railguns were something we were really going to go after, but it turns out that powder guns firing the same hypervelocity projectiles gets you almost as much as you would get out of the electromagnetic railgun, but it’s something we can do much faster,” as then-Deputy Defense Secretary Robert Work told lawmakers in May 2016. Indeed, a spokesman confirmed to me back in 2017 that SCO had “shifted the project’s focus to conventional powder guns, facilitating a faster transition of HVP technology to the warfighter.”
That insight changed not just the Navy’s strategy, but kickstarted a new cross-service effort to employ the HVP through existing gun systems. The Defense Department’s fiscal year 2017 budget request laid out plans for SCO to redirect its railgun work into the new Hypervelocity Gun Weapon System (HGWS), a joint effort with the Army, Navy, and US Air Force to explore employing the HVP from traditional powder-based field guns for a mobile point defense solution. In 2018, The Navy tested a fusillade of HVPs from the destroyer USS Dewey’s Mk 45 guns during the Rim of the Pacific (RIMPAC) international military exercise. And in 2020, the Air Force loosed off HVPs from an Army M109 Paladin howitzer and a SCO HGWS prototype1 against mock Russian cruise missiles during a demonstration of the service’s Advanced Battle Management System (ABMS) at the White Sands Missile Range in New Mexico.
“Tanks2 shooting down cruise missiles is awesome,” then-Assistant Secretary of the Air Force for Acquisition, Technology and Logistics (and SCO founder) Dr. Will Roper told reporters at the time “Video game, sci-fi awesome. You’re not supposed to be able to shoot down a cruise missile with a tank. But, yes, you can, if the bullet is smart enough, and the bullet we use for that system is exceptionally smart.”
Watch the US military test-fire the Hypervelocity Gun Weapon System:
The demise of the Navy’s railgun program in 2021 appeared to spell trouble for the HVP. Despite its successful tests, the Navy’s HVP program, renamed the Gun-Launched Guided Projectile (GLGP), was killed off in the service’s fiscal year 2022 budget request pending a SCO reevaluation. Indeed, budget documents indicate that SCO had declared its HGWS R&D efforts complete in the previous budget cycle.
But reports of the HVP’s death were greatly exaggerated. Budget documents show that SCO subsequently requested $108.15 million in fiscal year 2023, $94.3 million in fiscal year 2024, and $165.075 in fiscal year 2025 for HGWS R&D, indicating fresh interest in the projectile.
That renewed investment set the stage for a quiet revival. In late 2024, a BAE spokesman told Naval News that the Navy was conducting fresh tests of the HVP from destroyers at sea which “successfully demonstrated effects on a various number of airborne threats.” In early 2025, Inside Defense reported that this testing was likely part of the service’s new Major Caliber Anti-Drone Air Program (MADCAP) initiated to evaluate the viability of employing the projectile from Mk 45 guns against the kinds of drone threats increasingly menacing American sailors in the Red Sea. And this past June, Navy leaders confirmed in a joint posture statement to the House Armed Service Committee that the destroyer USS Jason Dunham had tested the HVP from its guns in August 2024 and April 2025 while deployed to the Red Sea in support of Operation Prosperity Guardian, testing that took place alongside the USS The Sullivans’ evaluation of AGM-114L Longbow Hellfire missiles and Coyote and Roadrunner interceptors as potential counter-drone solutions.
“The results of these tests showed these systems can be effectively employed to defeat group 3 drones in a more cost-effective manner,” the statement said. “All four of these systems are being evaluated further for technical and tactical maturity and the results of that analysis will determine what combination of these systems is deployed on the next carrier strike group headed for the Red Sea.”
While the outcome of that testing is unclear, signs point to relative success: the Navy requested around $24.7 million in fiscal year 2024 to buy 22 HVPs for fresh trials, according to budget documents, while the service’s fiscal year 2026 budget request calls for the procurement of 5 additional HVPs.
Now, the other services are following the Navy’s lead and looking to adapt the HVP for the fight on land.
Building off the 2020 ABMS demonstration and SCO’s HGWS research, the Air Force’s Strategic Development Planning and Experimentation (SDPE) office in 2023 laid out plans to rapidly develop and field its Gun Launched Area Defense Interceptor Against Threats and Raids (GLADIATR), a vehicle-mounted, C-130-deployable weapon system that fire off HVPs to provide a “near-term air defense against cruise missiles.” Unlike conventional interceptors that cost millions per shot, GLADIATR explicitly aimed to deliver a “cost curve flipping” option that emphasized scalable and affordable volume over exquisite lethality to deal with saturation drone and missile raids. (While budget documents indicate the Air Force awarded a $20 million R&D contract for the system through its Rapid Defense Experimentation Reserve program in fiscal year 2024, but there appears to be no additional funding planned through the service’s fiscal year 2026 budget request.)
The Army is pursuing an even more ambitious vision, actively leveraging both the Air Force’s GLADIATR and SCO’s HGWS efforts to develop another new air defense capability.3 The service has asked for nearly $150 million in R&D funding in its fiscal year 2026 budget request (up from just $30 million last year) for the development of the Multi-Domain Artillery Cannon System (MDACS), a rapid prototype effort consisting of the cannon system, HVP, and Multi-Function Precision Radar (MFPR) that’s designed to defend US troops from drones, cruise missiles, aircraft, and “other advanced air and missile threats.”
BAE received a contract to develop the MDACS in December 2024, with plans to deliver a full battery of eight of the artillery cannon systems and “no less than” 144 HVPs to the Army by the end of fiscal year 2027, according to the contracting notice. According to budget documents, the service plans on spending about $646 million total on the MDACS between fiscal years 2025 and 2027 in the lead up to a demo in fiscal year 2028.
Watch a Defense Department video on the Multi-Domain Artillery Cannon System concept:
It’s worth noting that MDACS is described in the Army’s fiscal year 2026 budget request as “a potential component of [the] Golden Dome of America” missile defense shield proposed by the Trump administration, nested within the Expanded Mission Area Missile (EMAM) program alongside the Integrated Fires Protection Capability - High Energy laser (IFPC-HEL), Integrated Fires Protection Capability - High Power Microwave (IFPC-HPM), and new Joint Laser Weapon System (JLWS). The system has been on the Pentagon’s radar as a “cornerstone” of the initiative since April, Inside Defense reports.
MDACS, if successful, would give Army maneuver units a powerful new countermeasure for short- and medium-range air threats without relying on expensive, finite missile inventories. And like its antecedent GLADIATR, it embodies the Pentagon’s growing desire for adaptable, cross-domain firepower that can scale across multiple theaters.
The second life of the HVP is a rare case of defense R&D salvage. Born from the ashes of a canceled program, the HVP appears adaptable, cost-effective, and versatile in a way few weapons can claim. Its ongoing integration into multiple services’ platforms underscores a deeper strategic shift: a recognition that high-volume, low-cost interceptors may be the only way to keep pace with the accelerating threat landscape of drones, missiles, and hypersonics.
Of course, the HVP’s fate is far from secure. SCO’s fiscal year 2026 budget request indicates that its own HGWS efforts have now terminated after receiving $64.8 million last year due to “congressionally directed reductions” suggesting that continued R&D now belongs to the individual services (although the $600 million funneled into SCO as part of this year’s “One Big Beautiful Bill” for the “acceleration” of key programs may change that). With hundreds of million spent on the HVP over the last decade, time will tell if the investment will actually pay off or if systems like MDACS will end up languishing in the dreaded “valley of death” between R&D and procurement.
But whether deployed from Navy destroyers or Army howitzers, the HVP is quietly emerging as a powerful interceptor for a new kind of battlefield. In an era of rising missile salvos, drone swarms, and fiscal constraints, the Pentagon is rediscovering the power of speed, volume, and versatility. The railgun may have fizzled, but its ammo lives as a potentially foundational component of future layered air defenses.
Once regarded as the magic bullet of a sci-fi supergun, the HVP is now proving to be something far more practical: a cross-service workhorse designed for the hard realities of modern war.
There are conflicting reports regarding the systems used during the ABMS demonstration. While the Defense Department stated that a SCO HGWS was involved, The War Zone reported that the exercise also saw a Mk 51 AGS mounted on an M110 self-propelled howitzer fire off an HVP.
As far as I can tell, the MDACS concept video and GLADIATR concept art are exactly the same, suggesting that the former is simply the outgrowth of the latter.
The story so far taken as a whole is DOD and Primes develop but if we want speed or quantity - we need both - bypass Arlington 20301 Trust Fund and off to the new breed with direct and committed multi year funding. VCs will provide 1940s renaissance of American industry if funding is committed for years.