Taiwan map

[War Man]

M16A3 is USN SEAL only.

No way, the m16a3 is in the army and marines, though hardly used.
The navy seals use the m4a1.

[Expendable Grunt]

M16A3

The M16A3 was a fully-automatic variant of the M16A2 adopted in small numbers around the time of the introduction of the M16A2, primarily by the U.S. Navy for use by the SEALs. It features a Safe-Semi-Auto (S-1-F) trigger group like that of the M16A1.

Some confusion continues to exist regarding the M16A3. It is often described as the fully-automatic version of the M16A4. Descriptions of the M16A3 that claim that it shares the M16A4's Picatinny rail are incorrect. This misunderstanding most likely stems from the usage of the A2 and A3 designations by Colt and other manufacturers of weapons before the official adoption of the M16A4. Colt used the "A3" designation in the hopes of winning military contracts as they also did with the terms, "M4" and "M5."

[War Man]

M16A3

The M16A3 was a fully-automatic variant of the M16A2 adopted in small numbers around the time of the introduction of the M16A2, primarily by the U.S. Navy for use by the SEALs.

Primarily it says, which means it is used in other units too, also the m16a2 came out long before the m4a1, so I think it is hardly used by seals now but more on the army and marines.

[Eddie Baker]

Primarily it says, which means it is used in other units too, also the m16a2 came out long before the m4a1, so I think it is hardly used by seals now but more on the army and marines.

EG is correct. The Army and Marines did not adopt and their regular infantrymen do not use the M16A3. The US Navy had them for SEALs and ship force-protection and VBSS units, but how many are out there now is undetermined; ship VBSS teams now use the Mk-18, primarily.

The M16A2 came out the same time as the Colt Model 720 series (14.5" barrel carbine), around 1988. The 720 series is the basis for the M4 carbine series; the 720 had a governed burst and an M16A2 upper receiver, the 723 had unrestricted full automatic fire and M16A1 pattern sights, and the 727 has the M16A2 upper with unrestricted full-auto. These carbines have actually been used since the late 1980s in US Special Operations Forces (seeing earliest known action in Panama in 1989) prior to the official designation of "XM4" or "M4," and were just called by the troops the generic name for "shorty" M16 variants: CAR-15.

The 727 was the basis for the flat-topped Colt Model 927 formally adopted by USSOCOM as the M4A1 or M4A1 SOPMOD in the early 1990s (94, I think).

So, the M16A2 having come out "long before" the M4A1 is a fallacy.

[War Man]

I'm pretty sure a few troops in army and marines have them.