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Repair depot markings


Even though this page is located within the section dedicated to M91/30 rifles and M38/M44 carbines, it covers a much wider area, giving a basic understanding of how the Soviet firearm refurbishment industry worked and what approaches were used. The provided information can be extrapolated to other firearms from that period. It also brings to light many markings that have had a lot of interest and discussion about them.

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General description


As mentioned in the general description of M91/30 markings, repair depot markings, stamped during firearm repair/maintenance, were:

- repair depot ID number/logo markings;
- operational markings and proof marks;
- quality control markings;
- markings related to the change of the rifle's/carbine's status (conversion to training rifle, or non serviceable condition)


Often these markings are called "refurbishment markings", however, it is more correct to call them "repair depot markings". The purpose of the markings that were stamped during firearm repair was not to show the fact that the repair took place (there were no "wood repair", "metal parts refinish", etc, markings, this was incorrectly stated by some earlier sources), their main goal was to record  which depot was responsible for the repair process.

Groups of repair depot markings were very similar to factory markings. Repair depot markings can be found on the barrel shank, receiver, and stock. Soviet approach for repair depot marking was different in different periods. Roughly all repair depot markings can be divided into two periods :

1) prewar/wartime/early postwar;
2) late 1940's - 1991.

The basic difference between them was that markings of the first group contained a repair depot number (or the military district abbreviation), while markings of the second group are based on geometrical shapes (symbols) without depot numbers. However, some exceptions exist - some depots used shape-style markings during the wartime period, and some postwar repair depot symbols contained their number, more details will be provided below. 


Repair depots/facilities types

Generally, firearm repair and refurbishment depots were divided into stationary repair depots and mobile repair workshops/depots which were located between Army units in field.

Stationary repair depots were divided into three main groups – Arsenals, Central Artillery Armament bases (CABV) and Artillery Armament bases (ABV).* During the prewar/wartime period there was a type of a depot called "military storehouse",  postwar this was changed to ABV. CABV and Arsenals were accountable to the Main Artillery directorate, ABV to military districts. CABV and ABV bases also had different subtypes. There were bases that only stored firearms or artillery shells while others has departments for firearm repair. Arsenals were the best equipped of the repair depots and were able to make any type of repairs.

* CABV (ЦАБВ, Центральная Артиллерийская база вооружения) and ABV (АБВ, Артилерийская база вооружения) are transliteration of Russian abbreviations for these repair depots.

Army unit mobile depots/workshops had several levels. According to the 1943 M91/30 and M38 repair manual, a unit gunsmith could replace damaged parts (if he had the necessary replacements) and make minor repairs of mechanical damage to the firearms. All repairs must be made in the presence of guns owner. Rifles with more serious problems were sent to regimental repair depots. Regimental repair depots repaired the same issues addressed by unit gunsmiths, and also installed parts with non-standard sizes such as bolt heads with longer locking lugs and taller front sights. They also produced simple parts like screws, shims, and pins, and made other repairs which were allowed by the locally available equipment. In case of a shortage of necessary spare parts, the use of parts salvaged from damaged rifles was permitted.

The next higher level of a repair depot was the Army Artillery repair workshops (ААRМ). The AARM were capable of some machining and adjustment operations – straightening bent barrels and adjusting different parts and mechanisms which require machining, turning, gunsmithing and welding. Some of these types of repairs could also be made by regimental and division depots if they had the necessary equipment. It was permitted to send firearm parts from regimental/division depots to AARM instead of complete rifles for repairs. The highest level of mobile depots was the Mobile Artillery Workshop (PАМ). They serviced Army groups, and were able to make any types of repair like the stationary Arsenals. There was also a unit called the Movable artillery repair and restoration battalion, which was in the reserve of the Main Artillery Directorate, and headed to locations of the urgent need of repair capacities.

Markings used by repair depots/facilities

So far, the only recorded markings of the movable repair depots belong to few PAM depots and one repair-restoration battalion, all others (from both above mentioned time periods) were stationary depot markings.


   Prewar and early wartime pattern markings

The earliest pattern of stationary repair depot markings, used on M91's, M91/30's, was a combination of the letter "P" (Ремонт, Repair) and a depot number (at least one depot also used "AБ" letters instead of "P", they stands for Artillery base in Russian), stamped on the top of the receiver tang or on the barrel shank,. Sometimes it was just a repair depot number within a shape stamped on the barrel shank. Some depots used both locations - tang and barrel shank, in these cases, the marking on the receiver tang is from an earlier period than the barrel shank marking. At least two depots, ABV#75 and ABV#25 (in 1941/1942 they became CABV) stamped their markings on the stocks. ABV #75 used a combination of a triangle and base number (P75), ABV#75 used star marking with a base number in it. Normally year of the repair at firearms was not stamped, but at least base  #75 did this. Also reapir year stamping was widely by different bases used at optics.

Examples of repair depot markings (ABVs) on the receiver tang.


Examples of repair depot markings (ABVs) on the barrel shank and stock.  ABV#24 marking is stamped on a PEM scope, ABV#651 - on a PEM side mount.


   Wartime and early postwar pattern markings


Based on observations, the style of markings was changed during the war - military district armament bases started to use military district abbreviation instead of the base number (*O pattern), where first letter was a location, and second was"O" letter (from Russain "Oкруг", district). The most famous marking of this type is the "MO" marking. It was used by a Moscow military district artillery armament base №38 in Pavlovska Sloboda since 1942. Interestingly, in 1942-1943 the base used both styles of marking - "MO" and "38". That is because a part of the base was evacuated to Vahrushevo in the Kirov region, so this base had two production areas. 

An important note about these letter markings - they did not indicate the military district where a rifle was used, they only indicate that a firearm was repaired by a particular district base.

Examples of the military district artillery armament bases letter markings.


*Image above show "ДВ-30" marking, which do not falls into "*O" pattern. There was a single military district in the USSR, which was called not as all others during the period when "*O" pattern markings were used. It was Far Eastern military district,during 1935-1945 it was called "Far Eastern front". Supposedly "ДВ" stands for Russian "Far East" ("Дальний Восток"). In this particular case "ДВ-30" is not a factory serial number, because originally rifle was unfinished barreled receiver, assembled and numbered by repair depot. C.A.O-125 marked rifle at the top left corner is the same case - unfinished barreled receiver, numbered by Central Asian District Military storehouse #20.

Also, bottom line show "star with small circle inside" marking. It has common style with "ЛО in star with circle" marking above. "ЛО"  belongs to ABV#75 of Leningrad military district. Same repair depot converted PPS-42 SMGs to cutaway guns, and those conversion carry this "star with small circle inside" marking. So highly possible star-dot can be attributed to ABV#75.

Current information about repair depots letter markings is very fragmented and incomplete, however, it is obvious, that these markings have a connection to the Military districts. There are still many unanswered questions about them - why did some military district bases use them widely, like MO, why others used them in a very limited fashion or did not use them at all. Why did all bases change the letter markings to shapes later but MO was used at least up to 1993. The "MO" depot was the only one between district bases that stamped the year of the repair near the rifle's production year. While this was not typical to other facilities, it is not a unique feature. For example, base # 75 stamped the year of the repair in the prewar period, and few depots also did this postwar near their logo.

*MO marked rifles were considered as something special for a long time, and existed  different versions about meaning of MO marking , like "Defence Ministry" (Ministerstvo Oborony), "Local Defence" (Mestnaya oborona") and others.

In fact, it's just a repair depot marking. It was also used on various other firearms, like the PPSH-41, DP-27, TT-33, M1895, Maxim MG, optics, other devices. Dates of the repairs that have been observed  M91/30's are 1942-1953, but the latest recorded date for the MO depot (ABV#38) is 1993 (MO93 marking on binoculars)

A good example of the wide variety of markings used by a single depot is the base in Tashkent (now in Uzbekistan). It existed since the Imperial times, in the early Soviet period it was called "military storehouse №20". This depot was a main district stock (base) of the Central Asian Military district. The earliest recorded marking for this depot is "Б20" (base №20). Then (exact date is unknown) this depot started to used the CAO marking, it was stamped on repaired firearms. There is a number of M9/130 rifles that had C.A.O. abbreviation as a part of their serial number. These rifles were assembled by the repair depot from barreled receivers that originally did not have a serial number. In the late 1940's, this depot was renamed "district base №60" and started unisng the "P60" marking. In the 1950's, the P60 marking was replaced with a  shape marking - diamond with lines, the base became a district base of the newly created Turkestan military district.

Different types of  base №20/№60 markings.


Identified ABV and CABV repair depots

Markings of unknown repair depots (pre-1950 period).

Markings of unknown repair depots (pre-1950 period).


As previously mentioned, currently the only recorded markings of movable repair depots belong to PAM units, and one Movable artillery repair and restoration battalion (ПАРВБ abbreviation in Russian).

So far, markings of only two PAM depots were found on M91/30 rifles - they are PAM-2 (Leningrad front) and PAM-6 (Far Eastern front). It's possible that other markings will be discovered in the future - there were over 15 PAM depots. It's possible that ПМ-1 and ПМ-3 markings (marked as unidentified at the moment) belong to PAM-1 (location unknown) and PAM-3 (Far Eastern front), but this has not been confirmed. Also, one of the collectors have VZ-24 with ПАМ-13 marking (3rd Ukranian Front) on the stock.

PAM-2 placed its marking on the stock, PAM-6 - on the receiver (there were two types of markings - ПАМ-6  and ПАМ-Ь).

PAM markings were used approximately since 1942 and up to the early postwar period (latest recorded PAM marking, found on binoculars, have a 1947 date).

PAM-2 (Movable reapir depot of the Leningrad front) marking on a stock.


PAM-6 (Movable reapir depot of the Far Eastern front) marking on a stock.

Photo courtesy of Brett A Overall.


Movable artillery repair and restoration battalion №167 marking on a stock.

Photo courtesy of Brad Chandler.



Postwar pattern markings


Prewar/wartime stationary repair depots markings are quite uncommon. The most common type of the repair depot markings nowadays are postwar repair depot markings. Starting in the late 1940's, Soviets started to unify repair depot markings. The vast majority of repair depots of different levels received unique markings based on the combination of shapes and sometimes numbers. The earliest recorded repair depot shape marking belongs to Arsenal #1. It was used since the late 1930's, the marking of the Arsenal #1 is well known to the majority of collectors, it's a box with diagonal cross line.

In 1942 Arsenal #3 in Tbilisi started to use a triangle with a circle inside symbol. Both mentioned depots did not use their markings on repaired firearms, they were stamped only on rifle parts that were produced by them (stocks, bayonets),  they were used like a manufacturer logo. Since the late 1940's more and more repair depots received shape symbols, they started to use them on repaired firearms. Repair depots had their own quality control departments, all repaired firearms had quality control and acceptance stamps. However, quality control and acceptance stamps are currently only identified for a few repair depots, some of these markings are shown below.

Arsenal #1 marking on the barrel shank and stock (box with one cross line). Marking on the stock does not always indicate a repair, quite often it indicated that stock was manufactured by the arsenal. Differences between factory and arsenal made stocks is described in the stock section.

arsenal1 main.jpg

On the left - Arsenal #1 repaired stock, on the right - Arsenal #1 produced stock


Acceptance markings that were used on Arsenal #1 made parts - on the left "АП" in a box acceptance marking that can be found on early postwar stocks, in the middle and on the right - crossed hammers marking (sometimes in a box) that can be found on stocks and bayonets


Quality control markings that were used by Arsenal #1 on repaired firearms. Typical style is "x-y" (in the box, oval, or without) where "x" can be 1,2 or 3, and "y" in a number from 1 up to 30


Arsenal #2 marking on a M91/30 barrel shank and on a trench periscope (box with two crosslines). Markings of this arsenal are quite common on PU scopes and on optics. Often (but not always) the depot marked the year when a device was repaired. Indication of the repair year was not used on firearms.
* During the late 1950's, the year of the repair on optics was coded by a single letter, more details below


Acceptance marking that was used on Arsenal #2 repaired rifles - C13 in tombstone marking (numbers other than 13 are possible). It is interesting that the famous "KO in a tombstone" marking was used by the Kiev military district artillery armament base #64. Arsenal #2 and base #64 were both located in Kiev.


Arsenal #7 markings on the barrel shank (box).

Almost always there is a quality control/acceptance stamp near it - circle with crossed hammers


Arsenal #7 also produced parts  for different firearms in addition to the regular repair - image at the top show markings on a DP27 (28) stock, produced by the Arsenal, on the bottom - markings on the M91/30 rear sight base. Arsenals often used those bases for the M91 dragoon to M91/30 configuration conversions


Lower level depots (Armament bases) also used different quality control/acceptance markings. An interesting thing about them (this also applies to Arsenals) is that sometimes they allow for the identification of a repair depot, even without the main marking present.

CABV #25 markings. The main marking of this depot, since the late 1940's, was the "25 in triangle" marking. As acceptance/quality control marking that was used is a small star (sometimes with a number inside, sometimes without), and a circle with number. The image on the bottom shows markings on a M1895 revolver.


A rifle without the main CABV#25 marking, but with an acceptance/quality control marking of this depot - small star.


CABV #75 markings on a M91/30 stock. The main marking of this depot was a "75 in a triangle" (during wartime an ЛО marking was briefly used). The acceptance/quality control marking was a circle with "OTK 75" (OTK - quality control department). Photo courtesy of Ruslan Klimovich.


Rifles without the main CABV#75 marking, but with acceptance/quality control marking of this depot - "OTK 75 in circle"


Famous "1 in triangle" marking(front right part of the barrel shank), which was earlier reffered as DDR marking.

In fact it belongs to former CABV #41 in Irkutsk (in late 1980's - arsenal).

Acceptance/quality control markings are located on the stock


All currently recorded post 1950 shape pattern repair depot markings, that can be found on M91/30's and M38/M44 carbines and other soviet small arms are shown in the table below. There are other existing repair depot markings, that are not included in the table, but so far they were not observed on Soviet small arms. If and when new information is discovered, the table will be updated


** Information about locations of the repair depots was taken from the open sources and earlier publications by other authors. Basic sourche - article by R.N.Chumak, Чумак Р.Н. К вопросу определения места ремонта стрелкового оружия по клейму (условному знаку) арсенала на нем. Война и оружие. Новые исследования и материалы. Труды Пятой Международной научно-практической конференции. 14–16 мая 2015 года. Часть 4. Л.433  

In the majority of cases, repair depot markings were stamped on the barrel shank, usually in the top/middle, but it can  sometimes be seen on the sides. Some repair depots stamped their markings on the receiver. Very rarely the year of the repair was stamped/engraved.

Sometimes repair depot markings can be seen on stocks, in various locations. They can indicate stock repair or production by a repair depot. Repair depot markings were stamped on storage crates. The repair depot marking doesn't always indicate that a  repair took place, sometimes it just means an inspection was performed.

Placement of repair depot markings on a barrel shank and receiver.

barre receiver markings.jpg

Placement of the repair depot markings on the stock.


Quite often rifles have numerous repair depot markings. According to instructions, during a rifles inspection/repair/overhaul, the earlier repair depot markings should be struck out or ground off. But in the majority of cases this rule was ignored, there are less rifles with strike out repair depot marking than without.

Rifles with an identical pattern of repair depot markings - "12 in a triangle", "T in a box", "box with vertical crossline". The rifle on the left has a struck out "T in a box" marking, on the right - it is untouched.

cancelled marking.jpg

According to instructions, at least since the early 1950's, all repair depots used the same marking, which was stamped on  repaired firearms. It is a marking that indicates adjustment shooting after repair, it looks like a "П in box". This marking was stamped near the factory logo. It was not used earlier than the 1950's, and clearly indicates that the rifle was refurbished postwar, even in cases where the main repair depot marking is missing.

"П in box" adjustment shooting marking. Barrel shank of the rifle on the right does not have a repair depot marking, but "П in box" indicates a postwar refurbishment.

proof shooting.jpg
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