Question: The 8×50mmR Lebel is a rifle cartridge that can be used in what rifle that had a bolt modification added in 1893?
Sentence (from "8×68mm S"): The 8×68mm S rebated rim bottlenecked centerfire rifle cartridge (the S denoting it is intended for 8.2 mm (.323 in) groove diameter bullets) and its necked-down sister cartridge, the 6.5×68mm (no S, or other modifier required), were developed in the 1930s by August Schüler of the "August Schüler Waffenfabrik, Suhl, Germany" as magnum hunting cartridges that would just fit and function in standard-sized Mauser 98 bolt-action rifles.
Relevant evidence: No