Originally Posted by DLiller
Why is it a big deal it fires from a closed bolt?
In the subgun world it is something to be liked. It's easier to make a submachine gun that fires from an open bolt (less chance of a round cooking off in the chamber). Problem is, having a heavy bolt slam shut before firing results in a loss of accuracy. Moreover, the ATF in the USA really really REALLY dislikes open bolt guns because it's easier to convert them to full auto.
By going with a design that fires from a closed bolt it's easier to hit the target and makes possible potential civilian sales for a semiauto only variant.