Ok... here.

https://www.reddit.com/r/insurgency/comments/wdol4l/brandnew_chinese_qbz191_assault_rifles_cant_put/

All I did was Google: Chinese gun keyhole. It's literally the first result and this is one of the videos I've seen before about this. There are others. It's really not hard to see for yourself. That is a clip from CCP run propaganda BTW. This is video made and submitted by the chineese government.