B-1Bs left the factory in the three tone strategic camoflage:
FS 36081 Gray
FS 36118 Gray
FS 34086 Dark Green

Depending on the lighting and weathering it is sometimes difficult to distinguish the differences in these colors.

Starting in the fall of 1990 the fleet began the move to FS 36118 Gunship Gray. For a bit (until 1992) the radomes remained 36081 Gray.

Source Rockwell B-1B, SACs last Bomber, by Don Logan, page 233