Your M/6 was made in or around 1923. The exact date can't be determined from the factory records we have found. You don't mention the type of action on the other rifle so it's a bit difficult to identify it, but I will take a guess. From the RW in the serial # I'm guessing it's a pump action 22??? If so, it was made in 1914.
One was found sticking up through the ground and is in working order? Those seem to contradict each other. I certainly would not want to shoot it after hearing that description. I doubt that there would be enough value to bother with insuring. Neither of the rifles are rare, but do have collector interest when in good shape.