The CR-21 was a private effort to create a new rifle for the South African military in the 1990s. Bullpup designs were all the rage at the time (Austria has the AUG, France had the FAMAS, the UK had the SA80, etc), and so a company called Lyttelton Engineering Works (now part of Denel Land Systems) created a bullpup conversion design for the South African R4 (Galil). It was given a very fluid, futuristic look, and equipped with a fiber optic optic without any iron sights. The action and magazines remained original R4/Galil, however
Transfer bar is the culprit, only the AUG designed stupidity into the trigger - who tf wants a two stage semi>auto continuous pull?
The long travel of the transfer bar inherently adds flex and slop, it’s tolerable in handguns because the movement isn’t very far and nobody expects 2MOA. It’s shows (and feels worse) on long guns that in conventional layouts are much better, even on a 5-7lb milspec gun.
Keltec pulled a big brain move on the RBD and had the trigger up front run the sear engagement, and transfer the sear movement instead of the trigger’s movement, but it’s still not the same