Description
25x40mm Aluminum Cartridge Case, Marked “207370-3” – Experimental U.S. 25mm Ammunition
This 25x40mm aluminum cartridge case is marked “207370-3” in white lettering on the side. Its compact dimensions and aluminum construction place it within the same general class of experimental U.S. 25mm grenade ammunition developed during the late 20th and early 21st centuries.
The exact 207370-3 marking has not been independently matched to a public U.S. military or contractor parts catalog. For that reason, it is listed as the visible case marking rather than being presented as a confirmed military part number, NSN, or DODIC.
Historical Significance
During the 1990s and 2000s, the U.S. military explored compact programmable grenade systems that could give individual soldiers the ability to engage targets behind walls, berms, and other cover.
One of the best-known programs was the XM25 Counter Defilade Target Engagement system, a shoulder-fired weapon using programmable 25mm ammunition. The fire-control system measured the distance to a target and could program compatible ammunition to function at a selected point in flight.
Experimental 25mm ammunition went through several changes during development. Case shapes, belt dimensions, materials, and projectile configurations varied as engineers refined the system.
XM25 prototypes were evaluated by U.S. troops in Afghanistan beginning in 2010. Development continued for several more years before the Army ended the XM25 program in July 2018.
A loose experimental case such as this is an interesting artifact from the broader period when the military was trying to combine advanced electronics with compact grenade-launcher ammunition.
What This Item Is and Does
This item is the aluminum cartridge case only from a 25x40mm-class cartridge.
In a complete cartridge, the case forms the lower portion of the round and contains the ignition and propelling components while supporting the projectile assembly.
Aluminum offered a useful way to reduce ammunition weight compared with heavier case materials. Weight was especially important for experimental infantry systems where a soldier had to carry the weapon, fire-control equipment, magazines, and ammunition.
This listing does not include a projectile, fuze, propellant, complete cartridge, launcher, or other ammunition components.
Identification and the “207370-3” Marking
The most useful identifying feature on this example is the white 207370-3 marking printed on the side of the aluminum case.
At this time:
- Caliber/case size: 25x40mm
- Case material: Aluminum
- Visible marking: 207370-3
- Marking color: White
- Exact manufacturer: Not confirmed
- Exact cartridge model: Not confirmed
- NSN: Not confirmed
- DODIC: Not confirmed
- Exact XM25 application: Not independently confirmed
The dimensions are consistent with the experimental 25mm grenade-ammunition era, but the marking alone is not enough to assign the case to a specific high-explosive, airburst, training, armor-piercing, breaching, or other cartridge type.
Key Features
- 25x40mm-class cartridge case
- Lightweight aluminum construction
- White 207370-3 side marking
- Experimental/developmental 25mm ammunition style
- Associated historically with the era of U.S. programmable 25mm grenade development
- Unusual short-case configuration
- Case only
- Exact round type and manufacturer not confirmed
- No unsupported NSN or DODIC assigned
Why This Item Matters
Experimental ammunition components are often harder to document than standardized service rounds because designs can change several times before a weapon reaches production.
That makes markings such as 207370-3 especially useful. Even when a public cross-reference is unavailable, the original marking preserves information that may help identify the component as additional technical records become available.
The short aluminum case also makes an interesting comparison piece beside conventional 25mm cannon ammunition such as the much longer 25x137mm M242 Bushmaster cartridge. Although both are nominally 25mm, they were developed for very different weapon concepts and should not be confused.
About This Item
This listing is for one 25x40mm aluminum cartridge case marked 207370-3.
The case may show scratches, finish wear, oxidation, staining, dents, handling marks, fading of the white lettering, or other signs of age and storage.
No projectile, fuze, propellant, complete round, magazine, or weapon is included.
Because the 207370-3 marking has not yet been located in a verified public military parts listing, we are intentionally not assigning this case to a specific XM25 ammunition model or describing 207370-3 as an official military part number.
Ideal For
- Experimental U.S. ammunition collections
- 25mm cartridge collections
- XM25-era weapon-development displays
- Programmable airburst ammunition exhibits
- Military research collections
- Cartridge-case reference collections
- Prototype and developmental ordnance displays
- Military museums
- Engineering and ammunition-development exhibits
- Comparative 25mm ammunition collections
Approx length 1.5", Approx width 1", Approx height 1", Approx weight 0.2 lbs.
Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item's general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.
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