Mauser Model 1896 9mm

[Jack]

I think PJGunner hit it- it was the first model Ross rifle that could be mis assembled.
The Ross was a straight pull bolt action, if I remember right, with a rotating bolt head. In the first model, if the assembly wasn't correct, the bolt would appear normal in closed position, and the rifle would fire, with the bolt head not rotated to lock it. Instant forehead ornament!
Ross corrected the problem with the addition of a pin somewhere in the bolt assembly. I can recall someone who collected Ross' explaining to look for the pin, but I can't remember where exactly- long time ago...
The Ross in 303 Brit was used by Canadian troops in WW1, and developed a poor reputation as a military rifle. Apparently the Ross design bolt didn't have enough camming power to extract some of the shoddily made cartridges that were used during WW1. But no problems with bolts flying out- that problem had been corrected by then.