Re: WRA 69 Brass
WRA with the last two digits of the year of production is the way Winchester's conglomerate marked its USGI contract ball ammo.
In 5.56 M193 stuff (pre-NATO adoption), Winchester had its WCC division making the mousegun ammo. They might have had others involved, too, but that's all I saw in that caliber. Headstamps are WCC with [XX] year opposite the WCC. All was ball, all was crimped that I've ever seen.
There's a lot more to USGI ammo production than LCAAP, especially during the Vietnam years--a small war in general, yet much larger an operation at its peak (more than a half-million troops IN THEATRE) than our current pathetic efforts to control Iraq and Afghanistan.
Back then, ammo was really in production, at multiple facilities.