Thanks for all the info guys. I will take some pictures of the breech and top of the barrels in just a bit but there doesn't seem to be any markings on them at all.
Also this could be very common, but the extractors only eject the shell that has been fired. For instance if two shells are loaded, one is fired, then you open the breech only the fired shell will be ejected.
They are called selective ejectors and are common. However the type of selective ejector system is what you look at for rarity, etc.
