“The M4E1 is a brilliant design & idea for an updated upper receiver. The free float hand guard mount being designed into the upper is a rock solid improvement. Barrel install is easy, depending on your barrel of choice. Some barrels are designed for a heated fit, it’s tough to heat this receiver up, so be sure to freeze your barrel over night so as to guarantee she fits in the receiver when it’s time to install.
Love the look of the M4E1, and the rock solid lock up between upper and free float hand guard.
Bomber!”
