505 Gibbs has been around longer then the 50 BMG itself. Vigilance Rifles offers the only Semi-Automatic rifle in world chamber in the 505 Gibbs. It holds five rounds and only weighs 17 lb. but puts out a 600 gn Bone Crusher bullet at 2250 fps. Over 6000 Foot Pounds of Energy.. Designed for the large game hunter to put the game down.
It just made sense to offer the VR1 in 505 Gibbs it is the parent cartridge for the Cheytac.