PICATINNY ARSENAL, N.J. – Army armament engineers here partnered with a pair of Pennsylvania companies, one with alloy expertise and the other with forging metals, to deliver a capable barrel for the Army’s next generation of small arms.

Carpenter Technology developed the alloy and Geissele Automatics (also known as GWYNEDD) developed the production techniques for the barrels, while the U.S. Army Combat Capabilities Development Command (DEVCOM) Armaments Center provided the expertise in gun technology to deliver an innovation that is key to meeting the required capability.

This novel barrel design, created as part of two separate CRADAs (Cooperative Research and Development Agreements) between the Armaments Center, Geissele and Carpenter, relies on the alloy, GNB 200, which provides Army small caliber next generation weapons with higher tensile strength and, with it, better wear resistance.

This advancement came after several projects focusing specifically on barrel technology over the past decade.

According to general engineer Daniel Cler, the design’s principal investigator, DEVCOM had tested several “high alloy barrel materials” over the decade, seeking to help alleviate pressure buildup, corrosion and mechanical wear as next-generation weapons maintain significantly higher-pressure than their legacy counterparts, this could in turn worsen barrel wear.

In the past several years, the U.S. Army has attempted to shift away from using hazardous heavy metals such as hexavalent chromium coatings, which is still renowned for its longevity, but is known to cause significant health problems in production when hexavalent chromium is in solution.

Seeking to replace hexavelant chrome coatings with barrel materials that provide good wear and corrosion performance without coatings, the Army has performed research into a plethora of different metals. However, many of these materials were too hard to cold hammer forge, a method that is the current manufacturing technology for most military small arms. Because of this, the Armaments Center was refocusing on hammer forging and materials that were compatible with the process when it signed both CRADAs in 2022.

GNB 200 is, per Carpenter Technology’s website, a “premium remelted alloy steel specially formulated for high temperature wear resistance.” According to Cler, GNB 200 is near the upper limit of what can reliably be cold-hammer forged.

Carpenter Technology was already highly familiar with GNB 200, and as such provided samples for testing, along with several other materials. The Armaments Center gave guidance, processed information, provided support for analysis and result documentation and carried out accelerated wear testing for proposed alloys.

Work with Geissele focused on manufacturability and feasibility. Geissele cold hammer forged the barrels themselves, provided input and direction for coating alternatives and specifications, performed testing on barrels, and processed parameters on manufacturability. In this stage, the Armaments Center gave its expertise on barrel technologies, provided ammunition for testing and performed project oversight.

The parties involved tested the barrels in an M240L machine guns over the project’s third and final year, which ended in spring 2025. The material showed much better performance than the standard M240L barrel and now informs future Army next generation weapons.

GNB 200 continues to inform the next generation of Army small caliber weapons.Though the CRADA with Carpenter Technology has expired, DEVCOM renewed its CRADA with Geissele for another three years to continue development of barrel coatings.

A CRADA is a written agreement between one or more federal laboratories and one or more non-federal parties to work together on research or development.

The GNB 200 hammer forged barrel is not the only project made in collaboration with Geissele. The pair also collaborated on developing a new rifle profile which has been shown to further reduce wear and improve dispersion. This profile received United States Patent 12,203,716 B2 on Jan. 21, 2025.

Cler said he was most proud of seeing a project he worked on informed next generation systems. He also noted how important it is to have some influence upon the industry in the correct direction, though he lamented not being able to get involved earlier.

“CRADA’s are a good way to influence industry so that as systems are developed to meet Army requirements, industry is ready to jump in with better solutions that are more aligned with the Army,” he said.

By Tyler Barth