No. The Wilson Combat AR-15 Billet Stripped Upper Receiver in .458 SOCOM takes only two caliber specific parts-a .458 specific bolt and barrel. It is designed to be used with only .458 SOCOM with an ejection port modified specifically for .458.
This can work with with standard Mil-Spec forged lower receivers or Wilson BILLet-AR lower receivers and any standard AR barrel.
The Wilson Combat AR-15 Billet Stripped Upper Receiver will work with an Aero Precision Forged Lower, if it has Mil-Spec dimensions.
Yes, the Wilson Combat AR-15 Billet Stripped Upper Receiver will work for 300 Blackout.
The manufacturer doesn't state that it does, but from my understanding all of the Wilson Combat receivers have the Armor Tough Coating.
Yes, the Wilson Combat AR-15 Billet Stripped Upper Receiver has a single feed ramp and modified ejection port for the .458 SOCOM.
Standard as in yes it will fit most lowers, yes.
No, you this is a big bore receiver.
This upper is not listed as 9mm, its either 5.56 or .458 socom.
Yes. The Wilson Combat AR-15 Billet Stripped Upper Receiver for .458 uses m4 feed ramps as well as some other specific features to .458 SOCOM like an Undersize bolt raceway for smoother chambering, improved feeding and enhanced recoil dynamics, and an ejection port modified for .458 SOCOM cartridge length.