OK, many of you collect US Army weapons, or have Army weapons or their civilianized counterparts (like AR-15s or M1As) in your collections. As you probably know, the Army publishes fairly good manuals about these guns, Field Manuals and Technical Manuals. Now, you can’t learn everything, unlike the German officers in Those Magnificent Men in their Flying Machines, “from ze manual!” but you can learn quite a lot, especially with the higher-suffix technical manuals.
Say what? Yes, there’s a code to these numbers but it’s a code you can break. Understanding these numbers will be a great benefit to you — even most soldiers, even armorers and maintenance experts, don’t understand this system.
To understand the manuals, you need to understand just a little about the Army maintenance system. The Army divides maintenance tasks by level or “echelon,” with the operator (or crew, for a crew-served weapon like a .50 MG or an M4 Sherman tank) at the bottom end and Depot Maintenance at the high end. Each higher level is authorized and required to do more. On an M16, for example, an operator can only clean and field-strip the rifle, although his unit armorer may let him replace broken handguards. The operator usually isn’t allowed do anything that would require him to apply a tool to the gun, or to remove a part that isn’t removed for normal cleaning. The Depot, conversely, can replace the barrel or any other part and completely overhaul and zero-time the rifle, preparing it for reissue as meeting new rifle specs.
In all there are five levels of maintenance, with the first two taking place at the unit level, and the top three going to increasingly remote, and increasingly well-equipped, maintenance organizations. These echelons existed in the same way in World War II as today, even though hardly anything issued then is still in the field. (The M2HB machine gun is an exception).
- Operator/Crew Maintenance (also known by code letter C)
- Organizational Maintenance (code letter O)
- Direct Support Maintenance (formerly “Field” maintenance, code F)
- General Support Maintenance (formerly “Heavy” maintenance, H)
- Depot Maintenance (code letter D).
The most common Army manuals are Field Manuals, which describe Army doctrine, and Technical Manuals, which describe equipment. So while an FM covers marksmanship training, when you want to maintain or repair weapons, you’ll be playing in the TM garden. Here’s a typical Army TM number: TM9-1005-317-10. Every single digit of that carries meaning!
To decode the manual, break it down into parts. “TM” obviously tells us it’s a Technical Manual and not an FM, Training Circular (TC), Graphic Training Aid (GTA) or some other kind of publication. The 9 tells us who’s responsible for the TM.
- 1 — Aviation
- 3 — Chemical
- 5 — Engineer
- 7 — Infantry
- 9 — Ordnance (now called the Tank & Automotive Command, it’s also responsible for small arms)
“1005″ is a code for the Federal Supply Class of the manual’s subject. One of these numbers appears in the National Stock Number/NATO Stock Number of any item in the supply system. The numbers you’ll be most interested in with respect to weapons are:
- 1000 — small arms, general
- 1005 — Small Arms up to and including 30mm
- 1010 — Small Arms above 30mm
- 1340 — Anti-Tank Weapons
- 6920 — Training Aids and Devices
It’s obvious that 1005 is the sweet spot for gun collectors, including as it does every shoulder fired weapon between .22 and 30mm, and a TM-9-1005-anything is going to be useful to us. Crossing the next hyphen brings us to a three-digit number, in the case of our example 317. Now this is the identifier of the particular end item, and you have to know these numbers, or be able to look them up. We happen to know that “317″ happens to be “Pistol, Semi-automatic, 9mm, M9,” the standard GI version of the Beretta 92FS. (OK, the manual’s sitting in front of us. So, for that matter, is the pistol). The pistol’s NSN, by the way, is
But decoding NSNs is a question for another day, perhaps. You do recognize the FSC of 1005 is the leading segment of the NSN. All firearms will lead with 1005, unless they’re big enough to be 1010 (common examples of the latter are the M79, M203, M320 and Mk19 grenade launchers).
There’s one area left of the manual number, and that’s -10. And that’s depressing news, because it’s only the basic operator’s manual. Remember the five levels of maintenance? Yep, a dash-ten is user (operator) maintenance only. Dash-twenty’s organizational, Dash-fifty’s the depot manual.
Here’s the manual in .pdf form for download: Berreta M9 9mm TM_9-1005-317-10 The Army’s been trending away from paper pubs for 25 years, but older small arms manuals, at least, still come both ways.
Some manuals don’t end in “0″. The last digraph might be -12 (pretty common), -23, -45 or even a trigraph like -25P or even this strange arrangement: -25&P. What this means (taking the examples in order):
- -12: Echelons 1 and 2, so, operator or crew and unit maintenance;
- -23: Echelons 2 and 3, so, unit and direct support (WWII-era “field”) maintenance;
- -45: Echelons 4 and 5, so, heavy and depot maintenance;
- -25P: Echelon 2 through 5 Parts manual. This contains none of the maintenance procedures, but all of the parts (this is usually found with parts and tool lists. Special tool listings for higher echelon maintenance look promising, but the tools are listed by NSN — it’s usually a challenge to find them that way at Brownells’s or wherever).
- -25&P: the ampersand indicates that this manual contains the parts & tool list and the maintenance procedures for the item in question. This is a good manual to have, if it’s published for your weapon!
Not all manuals are made for all echelons. For some small arms items, the government has negotiated extended warrantees and sometimes just sends a gun or weapon sight back to the manufacturer and lets them sort it out or exchange a new one.
And of course, not every NSN has a manual, only major end items (a replacement M9 locking block — a very popular service part — has an NSN but it’s covered in the maintenance manuals). And some NSNs, especially way-complex systems from the era of paper manuals only (the old Shillelagh missile system springs to mind) have multi-volume manuals, with the volumes distinguished by a slash and number at the end of the TM number, /1 for example.
This article draws on personal experience, but was based solidly on Chuck Ruggiero’s Armorer’s Manual, a 1998 document used in armorer training in the National Guard and elsewhere. Highly recommended, and almost mandatory for an Army armorer (even though there’s no specific training course for unit armorers, there should be, and an updated version of this should be the textbook).
One last comment: the longest-running and most bitterly-fought war the USA has ever seen has been the battle between the Army and Navy, which has raged unchecked since 1775. Thanks to that kind of interservice squabble, every service has its own manual numbering system, but because most services use the same weapons, they have for many years used same manuals, with the sole inter-service concession of up to five manual numbers stamped on each cover (see the M9 operator manual in this post for an example). Therefore, you only need to learn one system to find almost all manuals in US service.