Help Identifying strange C96 mauser barrel

[srv335]

I bought a bunch of Mauser and c96 and Luger parts recently and got this in the lot.
It looks like a c96 barrel but the underside is completely different?
does anyone have a clue what it is? there aren't any markings on it to tell me anything?
What really kills me is its in really nice shape and the bore is like new!
Any help would be really appreciated,
thanks in advance

 

[GCBurner]

Could it be one of the reworked Mauser "Schnellfeuer" M712s that Federal Ordnance inported from China some years back? They converted them from 7.63mm Mauser to 9mm Parabellum by cutting off the worn-out barrels and sleeving and welding a new 9mm barrel to the stub.

 

[srv335]

Yea but look at the bottom where it is supposed to slide on the lower, it can't slide on , i can't even figure out how it mounts?

 

[GCBurner]

Some of the imports were deactivated, so they couldn't be fired, and fitted on a dummy frame for display purposes only.

 

[srv335]

If anyone cares for future reference,
its a Barrel for and Astra 900 c96 copy.