Since some have not gone back to read my previous posts, I added this to the first one, to hopefully make it more clear about the transition from .30-06 to 7.62x51mm NATO.

----- 1903A4 rifles in Vietnam ----------------------

At the early part of the Vietnam War, 1903A4 Springfield sniper rifles with the M84

telescopic sights were used, same as in the Korean War. There were not enough of

these, which is why you see photos of snipers and sharpshooters with Model 70

Winchester and Remington 700 ADL sporting rifles, usually in .30-06. The 1903A4 rifle

continued to be used into the 1970s.

The training manual is FM 23-10.
The technical manual is TM 9-270, dated September 1943.
The last revision of the TM 9-270 is Tm 9-1270, dated December 1970.