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- XM109 (US - Semi-Auto Rifle - 25 × 59 mm Grenade)
- XM174 (United States - Grenade Launcher - 40×46mm)
- XM177 (United States - Assault Rifle)
- XM214 Minigun (United States - Gatling Gun - 5.56×45mm NATO)
- XM25 (Germany - Grenade Launcher - 25×40mm)
- XM8 (Germany - Assault Rifle - 5.56×45mm NATO)
- XM307 (United States - Interchangeable Grenade Launcher/Machine Gun - 25×59mm/.50cal)
- XM312 (United States - Heavy Machine Gun - 12.7×99mm NATO/.50 BMG)
Read more about this topic: List Of Firearms