I also think the shape of the bolts arm and proximity to the receiver limits how it can be manipulated in its current state. I think it was intended to be used with the palm as the acting member, not the fingers. The guides built in to the shroud to prevent binding suggests they envisioned this sort of gross motion, which may have been more successful than hunt and manipulate with the digits.
Just guessing here. I'll go back to my ak now.
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