"General Liu rifle" is the unofficial designation for an undesignated Chinese prototype self-loading rifle.
Named after its designer, the first Superintendent of the Hanyang Arsenal, Liu Qing En, the rifle's development started around 1914 when Liu contacted Pratt & Whitney Measurement Systems of the United States to purchase equipment for his company.
Two versions of the rifle were produced by 1916 and tested at the Nanyuan Proving Grounds; one of them being made by the Hanyang Arsenal and the other made by Pratt & Whitney, with the Pratt & Whitney version proving to be superior due to differences in driving springs between both versions. Two more rifles (or possibly the same two tested in 1916) were tested again by the Springfield Armory; nothing was heard from them after the tests, so the rifle was essentially shelved.
Only a few rifles were produced, though it is unclear how many actually were produced. One known sample is known to survive in the Swedish Armémuseum, and another survives in the Springfield Armory Museum.
This self-loading rifle used a gas trap system à la Bang rifle and Gewehr 41. Inside the rifle included one driving spring to drive the action; those made by the Hanyang Arsenal had handmade driving springs while those made by Pratt & Whitney had machined driving springs.
A rather interesting quirk about the rifle is its ability to be converted into a bolt-action rifle if the user so desired, à la Gewehr 41(M), by rotating a cylinder on the muzzle counter-clockwise. The function was added so that the weapon would not be rendered useless if the gas system ever did fail.