We’re looking at a declassified report from the US Army Weapons Command in 1968. The report is available to subscribers to Small Arms of the World in their archives. And we came across the following little gem, which we’ve already served with several Vietnam-SF buds. Emphasis ours:

The first USAWECOM survey team stayed in Vietnam from 21 October1965 until 2 December 1966. (4) While the primary purpose of the team (5) was to provide maintenance instruction to a nucleus of officers and men from each brigade, who would then teach their own units, direct support organizations wece also instructed.

The team taught maintenance in every major USARV unit except the 1st Air Cavalry Division. (6) Students brought their own weapons, magazines, ammunition, cleaning materials, and accessories to class. A detailed inspection of each student’s equipment revealed that with the exception of the weapons of the 1st Brigade, 101st Airborne Division, the 173d Airborne Brigade, and the 5th Special Forces, all the weapons were poorly maintained.

The footnotes (4) and (5) refer to the team’s report and describe the makeup of the team — led by an ordnance LTC with four experts from USAWECOM and three from Colt. Note 6 explains why the Cav wasn’t trained — they said they were having no trouble with the M16A1, and asked only for instructors to work with its divisional maint battalion small-arms shop.

So what was jacked up about the GIs’ guns?

The most common faults observed were:

  1. Excessive oil on the weapon
  2. Carbon buildup in the chamber, bolt, and bolt carrier group
  3. Overloading of magazines with 21 rounds of ammunition
  4. Oil and grit inside magazines (frequently accompanied by lubricated ammunition); and
  5. Failure to replace worn or broken extractors and extractor springs.

Other deficiencies noted frequently were shortages of technical manuals, cleaning equipment, and repair parts, and a general lack of knowledge of the M16 rifle among officers and noncommissioned officers.

At first, it may seem strange that soldiers were unfamiliar with their weapons, but you have to remember how this report fits into American small arms history. The M16A1 was a standard — in Vietnam, only. The rest of the Army still soldiered on with the M14, and an awful lot of people in Army Ordnance still had their noses out of joint that Westmoreland had ordered a lot of weapons that were Not Invented Here (the M14, like the M1 before it, was developed in-house by the Army). Some of them wanted the M16 to go away. Others wanted it to fail. Still, others were captivated by the small-caliber, high-velocity concept and the M16’s brilliant ergonomics, and determined to help make it work. And many were of a type with Army men of all nations and all times: given a mission, intent on carrying it out.

We thought it was interesting that three airborne units (the 101st was still nominally Airborne at this time, although it would only have the name as n honorific by the time it left Vietnam) had few worries with their M16s, although it seems like the 1st Cav didn’t either. So why were the airborne units squared away, when most of the legs weren’t? Turns out that it wasn’t due to the higher quality of troops in the supposedly all-volunteer paratroop units, but had a more mundane explanation:

The 1st Brigade, 101st Airborne Division, the 173d Airborne Brigade, and the 5th Special Forces were the only units surveyed that had received training with the M16 for a significant period of time prior to deployment to Vietnam. Men in other units had been given training in marksmanship but little or no instruction in care and cleaning of the rifle.

On a follow-up visit, intended to cover maintenance of the very maintenance-intensive XM148 grenade launcher, a subsequent team discovered that many of the M16s turned in for maintenance (which might not be typical of all M16s in the field; a working weapon doesn’t get turned in for maintenance) had pitting in the chamber. They did the math and came up with a statistical prediction that 10% of all 16s in Vietnam would need a replacement barrel every three months. That correlated nicely with field complaints of extraction and ejection problems. One answer was to add chrome plating to the chamber (later, the whole bore) of all M16A1 rifles, and this report seems to be where that suggestion was first committed to official writing. This suggestion was not exactly rocket surgery: at the time, the Russians had been doing it for 20 years.

The chrome chamber weapons have “MP C” or “C MP C” markings on their barrels. The later Vietnam-era chrome bore weapons are marked “C MP B.” After the war, the marking changed to “C MP CHROME BORE” and that’s what most of the small supply of surplus M16 barrels say. The bore chroming is not a sign of a particular model of M16, it’s simply a running change, one of many hundreds

A lot more interesting stuff in this report. There is a CYA aspect to some of it, for sure, but it’s a window into a problem (M16 Jamming, circa 1966) of which much has been written, usually without reference to primary sources like this.

This entry was posted in Rifles and Carbines, SF History and Lore, Weapons Technology, Weapons that Made their Mark on by Hognose.

About Hognose

Former Special Forces 11B2S, later 18B, weapons man. (Also served in intelligence and operations jobs in SF).

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Daniel E. Watters

Most of the 12 volume “Report of the M16 Rifle Review Panel” is available for free download via DTIC. There are only three or four volumes that remain to be digitized in PDF format.