Posted: 12/31/2002 4:50:57 PM EDT
I am new to AR technology and I would like to know the differences in AR uppers relative to A1, A2 and A3.
Welcome aboard Stogieman.
The A1, A2 and A3 designations usually are in reference to the type of rear sights used.
An A1 upper has the windage adjustable only rear sights. This is what was used on the original AR15's and M16's, though the M16A1 also had the forward assist.
A2 has the elevation and windage adjustable sights.
A3's are the flat-top receivers for easier mounting of scopes. Removable carry handles are available with the A2-type of sight.