I received my LMT lower half today, and I noticed that the receiver extension nut seems to be staked in place (pictures to come later if needed). Sections of the receiver plate are jammed in the little notches of the nut, somewhat like how LMT secures their carrier keys.
My initial impression (and I am rather new to AR's), is that this seems rather shortsighted. What if the user wants to change the buttstock system? It's no big deal for me, since I really like LMT's SOPMOD stock. However, how am I supposed to change out the plate for a sling loop? I know I can probably just use a punch and hammer to free the nut, but still, if I wanted a lower half that I had to modify, I could have just gotten an MT6400C lower.
(Of course, I can understand if LMT meant for their products to go straight into the field and wanted to take preventive measures.)