It has the appearance of a grenade rifle, but with a red and yellow Chinese flag design on the stock. It was brought in as a gift for a general in the United States military and is found with a number of 40mm grenade rifle rounds.
The Red Victory grenade rifle originally appeared as cut content texture and meshes in the game files of Old World Blues, named as spider rifle, along with the projectiles.
The only way to obtain it is to nuke the Legion at the end of Lonesome Road.
This weapon does less contact damage with its grenades than the Great Bear grenade rifle, but makes up for it by being lighter to carry. Although considered to have a faster firing speed, both weapons are 1 shot and have identical reload speeds, making the issue moot.