This pistol recently surfaced from the estate of a former Mauser employee.
The basis appears to be an Interarms contract .32 ACP pistol that had the serial number removed and replaced with number V3, a serial number used by the R&D Department of Mauser (V for 'Versuch / Versuchsabteilung'). The barrel is a 9mmK / .380ACP version and the springs also are a bit stronger than usual. The hammer protrudes slightly further, so in order to remove the slide, the hammer must be pulled back slightly.
The slide and barrel have no proof markings, also no FBM markings. The frame is only FBM-marked and has no commercial proof (which one would expect in Germany, as it is legally required there).
The pistol itself is an early 1st variation, with the leaf spring disconnector, production somewhere in 1968 - 69.
Plastic grips are the early 'Mauser' type, not the AE Interams contract version.
I suspect that this pistol was somehow used as a 9mmK / .380ACP testbed, created by modifying a .32 version that was taken directly from regular production.
