That's a Swedish K...
I know this, because I carried one, along with an Inglis-made Hi-Power.
Ruger Blackhawks were 'very' popular - especially with Cav's helicopter pilots, as it added to the swagger, what with the Stetsons and spurs - but in the early days of that war, you saw a lot of privately-owned weaponry.
Later, it got a bit more staid as the older guys rotated home and were replaced by the ticket-punchers who really liked rules, but for awhile, it was the Wild West, and you carried what you could find, if you could get ammo for it.
A lot of locally-made holsters were produced - and they're a collecting field all their own, today.
Dix was serving as an Advisor to the ARVN - assigned to 5th SF.
Here's what he did...
The President of the United States in the name of the Congress takes pride in presenting the Medal of Honor to Staff Sergeant Drew Dennis Dix United States Army for service as set forth in the following citation:
For conspicuous gallantry and intrepidity in action at the risk of his life above and beyond the call of duty. SSG. Dix distinguished himself by exceptional heroism while serving as a unit adviser. Two heavily armed Viet Cong battalions attacked the Province capital city of Chau Phu resulting in the complete breakdown and fragmentation of the defenses of the city. SSG. Dix, with a patrol of Vietnamese soldiers, was recalled to assist in the defense of Chau Phu. Learning that a nurse was trapped in a house near the center of the city, SSG. Dix organized a relief force, successfully rescued the nurse, and returned her to the safety of the Tactical Operations Center. Being informed of other trapped civilians within the city, SSG. Dix voluntarily led another force to rescue eight civilian employees located in a building which was under heavy
mortar and
small-arms fire. SSG. Dix then returned to the center of the city. Upon approaching a building, he was subjected to intense
automatic rifle and machinegun fire from an unknown number of Viet Cong. He personally assaulted the building, killing six Viet Cong, and rescuing two
Filipinos. The following day SSG. Dix, still on his own volition, assembled a 20-man force and though under intense enemy fire cleared the Viet Cong out of the hotel, theater, and other adjacent buildings within the city. During this portion of the attack, Army Republic of Vietnam soldiers inspired by the heroism and success of SSG. Dix, rallied and commenced firing upon the Viet Cong. SSG. Dix captured 20 prisoners, including a high ranking Viet Cong official. He then attacked enemy troops who had entered the residence of the Deputy Province Chief and was successful in rescuing the official's wife and children. SSG. Dix's personal heroic actions resulted in 14 confirmed Viet Cong killed in action and possibly 25 more, the capture of 20 prisoners, 15 weapons, and the rescue of the 14 United States and free world civilians. The heroism of SSG. Dix was in the highest tradition and reflects great credit upon the U.S. Army.[SUP]
[2][/SUP]