Hmmm I've never heard of a black diamond 'explorer', so I can definitely see where it might be confusing
The two models are almost identical as far as I know, one of the only differences being the stock used. Not sure if the barrels have the same twist rate
The NW Explorer was just marketed as the solution to the NW ML regs problem, I believe the BD came out prior to that, yet filled that same type of void.
Wish I wasn't at work so I could check some, d*mn IT filters