Hoot,
We know from the research of others where the Mauser numbers will be found on those that they sold to "the trade", and I based my opinion on that. You could very well be correct that the other number is M&V.G. Since the barrel also has the Mauser number, it was likely sold by them as a barreled action, rather than a bare action. Mauser had patent rights and no one else could make them, so everyone had to buy from them. After WW1, the world was "awash" with surplus Mausers and most gunsmiths just used them. BTY American 8x57 ammo is loaded to be safe in the I bore guns, I have some Remington factory bullets that are really only .3215", instead of .323".
Mike
