Yep, they make that same upper with standard threads as well.Hi, Merle.
Are you sure you have an M4E1 Aero Precision upper and not a standard Aero Precision M4?
I just purchased one (M4E1) last week and the AP Atlas R one and S one will not fit due to the design of the E1 upper.
Had to go (fatter) Enhanced Handguard.
I would have rather had the slimmer R one or S one but standard M4 uppers are hard to come by right now.
Nice rig you built.
John.
M4E1 upper
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