Thanks for these helpful information on the books - you surely did a lot of reading on this subject!
Now here is the translation of that little memoir article on armored force of Sheng Shicai. This article is orally dictated by a former officer of Sheng's armored squadron and appeared in the book 阜康文史资料选辑 第三辑. The information on its equipment is extremely interesting but maybe not entirely reliable.
"After the military coup on April 12th, 1933, Sheng Shicai seized the governing power of Xinjiang. In order to reinforce his rule he expanded the provincial armed force, christening it 'the Anti-Imperialism Army'(反帝军). The army's equipment and training were all provided by the Soviet Union. This was the political background of the founding of Xinjiang's armored squadron.
"I graduated from the Army Officer School of Xinjiang in 1937 and started to work as a vehicle commander(second lieutenant). Later I was successively promoted to platoon commander(lieutenant) and company commander(captain).
In its early days the armored squadron was called armored battalion and was directly commanded by Xinjiang Border-Defence Command. Later it was transfered to Xinjiang's mechanized brigade and was changed into an armored squadron. The brigade commander before 1942 was Sheng Shiqi(Sheng Shicai's younger brother), after that was Liu Shixin; the commander of the armored squadron was Guan Yuliang. It consisted of a tank company with 11 Soviet tanks, an armored car company with 11 heavy armored cars(6 of them was made in Soviet Union, 5 of them were WW1-vintage German armored cars(sic)), an reconnaissance platoon with 4 light armored cars, a truck squad with 10 Soviet ZIS trucks and a special repairing squad.
Tanks and heavy armored cars had 4 crews - commander, driver, gunner and assistant; they were armed with one small cannon and one LMG. The light armred cars had only 2 crews, commander and gunner. The cannons were all fired by foot paddles. Spare parts, ammunition, uniform(that was, lether jackets), belts and map bags were all supplied by the Soviet Union.
"The training of the armored squadron included both class teaching and field training, and Soviet textbooks were used. Two Soviet military instructors named Constantinov and (I don't know how to translate the latter one's name) were sent in 1938 and were responsible for the teaching. The content of the classes included armored tactics(attack, defence, terrance, armamemt operating, etc.) and vehicle construction. After the Western Route of Chinese Red Army arrived in Urumqi it was codenamed 'the battalion of new recruits', and some of their soldiers were also sent to the armored squadron for learning purpose.
"on April 12th(the anniversay of Sheng Shicai's coup) of every year there was a parade of teh armored squadron and the related exercise began even before April. This also worked as a test for the armored squadron's training effort.
"I paticipated in two fightings in Xinjiang's armored squadron. The first is in Summer 1937 in Aksu, South Xinjiang. The heavy armored car company and reconnaissance platoon took part in the action in Aksu and Wensu County. The light armored cars of reconnaissance platoon under my command was located at the airfield of Wensu and was assigned the task of guarding the airfield. At that time Ma Husan(马虎山) and Mamuti(麻木提) had already started their rebellion against Sheng Shicai, and there was intense fighting between a brigade of Ma Hushan's army and a regiment(and it did not have enough men) under Sun Qinglin. Six BA-6 armored cars of the heavy armored car company participated the fight under the command of Guan Yuliang, and Sheng's force also had three aircraft to their aid. After 1 hour of fight Ma Hushan's force retreated in defeat, but there was also heavy casualty on our side, and squadron commander Guan Yuliang was killed in action.
"After that we were still stationed in Aksu until Ma Hushan went abroad in exile and Mamuti was defeated, then we returned to Urumqi.
"The second fight took place in autumn 1941 when there were bandit activity in Altay area. Four light armored cars under my command were sent to suppress the bandit. We exchanged fire with the bandits as soon as we arrived at Urungu River and the bandits were quickly dispersed. We were responsible for Altay's security fo some time after that, before eventually returned to Urumqi. "
My note: Photo evidence confirms that Xinjiang's armored squadron have BA-6 and BA-27. According to the recollection of a former soldier of Chinese Red Army who trained in the armored squadron, they have FAI, BA-6 and BA-27 armored cars. It is highly possible that the "ww1-vintage German armored cars" mentioned in this article were actually BA-27. Also, this is the only source mentioning Soviet tanks used by Sheng Shicai's force I have found so far, were these tanks T-26s or BTs? Very intriguing...
