Collectors that have some knowledge about Soviet 91/30 rifles have likely heard about "ex-sniper" rifles. This term mainly indicates rifles which at one point had a factory installed sniper scope mount and base, but, postwar, they were converted to regular rifle configuration by Soviet repair depots. During rework, the mount base was removed and the screw holes were plugged and welded over.
There are always disputes about why this was done. To bring some light onto the subject, we should look at what happened in 1945. At the end of 1944 the Soviet Union already had exccessive firearm production, the majority of newly produced weapons were sent to storage bases, not to the troops. 1945 M44 production was only at a 40% level of 1944 production, M38 production - only at the 15% level, regular rifles and sniper rifles were not produced at all (except a few guns for special purposes, only 1,250 sniper rifles were accepted from 1944 production).
After the war the Soviets had a huge amount of firearms, they were suppose to decide what they should do with them, especially considering that huge efforts were put into the construction of new semi-auto and full auto weapons. Starting at the end of 1944, all military units in the Army received questionnaires where they were asked about their opinion about different firearms, issues that they came across during their use and possible suggestions about weapons modernization.
A special questionnaire was given about the use of sniper rifles. It contained 37 questions about sniper rifles themselves, optics, tactics, ammunition, experience of use and so on. It also had a question about which sniper rifle, the PU, side mount mod. 1936, top mount mod 1931 or SVT sniper had the best performance. While military units sent their responses starting at the end of 1944, the general results were summarized only after the war ended, in December 1945. Every weapon type used by the Red Army during World War II was analyzed in detail, their strong and weak aspects were described. Recent and supposed modernization's were also mentioned, the further destiny of this weapon in the system of armament was described
According to the information which was received from military units, the PU sniper was considered as the best sniper rifle. While some military units pointed to some advantages of the PEM scope, the general preference was on the PU sniper side. The final conclusion of the Main Artillery Directorate, which was the governing body in the firearms area, was "leave PU sniper in the service until the end of the stock".
Leaving only the PU sniper in service, the Main Artillery Directorate defined a short life for the other sniper models in the Army. PEM and PE snipers, like any other weapons, required repair and maintenance. PEM scopes were not produced for a long time, so a source of new replacement parts was not available. Restoration of production was senseless, considering that PU sniper was selected as the only sniper rifle remaining in service.
Due to that decision, PEM and PE snipers were slowly recalled from troops. In the late 1940's and early 1950 they still were present in service in limited numbers, PEM scopes, rifles and mounts, were repaired using donor parts (there exist a number of PEM scopes and mounts with postwar repair depot markings), however, since the early 1950's only PU snipers remained in use with the troops.
PEM scope with a 1954 Arsenal #7 marking
As mentioned in "Models guide", every sniper rifle had its own Main Artillery Directorate code, which was also used during storage. After analyzing information from various sources (some of them related to the weapon storage system in the Soviet Army), it's safe to assume that PE and PEM sniper rifles were not put into storage in regular sniper configuration. Some quantity of scopes and mounts were put to storage separately (they sometimes still pop up from Russian stock), these sniper rifles were converted to regular rifle configuration and became "ex-snipers". While conversion of PEM and PE snipers can be easily explained, why is there a big number of PU snipers, that were left in service, found among the PE and PEM ex-snipers? I will try to give an explanation.
Repair depots had special instruction about the conversion of sniper rifles to "ex-snipers". Until now, the earliest instructions that were found are dated 1948 (officially adopted in April 1949), the document was created by the Separate Construction Bureau of Main Artillery Directorate. It describes, in detail, how rifles were converted, has drawings of mount plugs and repair inserts for the stock. It mentions only one reason why PU sniper rifles were converted - " if sniper rifle does not match accuracy standards", it is underlined and written with a bold font. However, the information found in this instructions is contradicted by actual observation - many of the surviving PU ex-snipers have perfect bores and show good shooting results. So how can this have happened?
Sniper rfile conversion drawings ("Drawings for the conversion of 7.62 sniper rifle to regular M91/30 model rifle")
Excerpt from drwawing which show only one reason of the conversion - bad accuracy
Drawing showing how plugs were installed and welded
Former PU sniper rifle with removed scope mount base, plugged and welded screw and pin holes.
Typical "ex-sniper" configuration. Photo courtesy of Walther Miller.
Former PE top mount round receiver sniper rifle with removed scope mount base, plugged and welded screw holes. Typical "ex-sniper" configuration. Photo courtesy of Phillip Gorny.
Former PE top mount hex receiver sniper rifle with removed scope mount base, plugged and welded screw holes. Typical "ex-sniper" configuration. Photo courtesy of Phillip Gorny.
Former PEM side mount sniper rifle with removed scope mount base, plugged and welded screw holes. Tula factory pattern. Photo courtesy of Phillip Gorny.
The majority of rifles, including sniper rifles, were refurbished during the late 1950's - 1960's. At that time new firearm models were accepted into service, this meant the magazine fed M91/30 rifle was already obsolete. The M91/30 accuracy depends not only on the bore condition, it also greatly depends on action and stock alignment and clearances between them. Considering the method of refurbishment that the Soviets used (parts were mismatched), sometimes serious adjustment was required. Situations arose where a PU sniper with a good bore was not accurate enough during tet shooting after refurbishment.
Now we should remember the 1945 conclusion - "left in service until the end of stock". Repair depots had no goal to keep as many snipers in storage as possible, and it was not a big issue if the number of available rifles was reduced, they still had tens of thousands. Cases happened, when instead of precise adjustment of the stock and action, a rifle was considered as inaccurate and was converted to an ex-sniper. In the end, the rifle remained in storage, but in a different configuration. Mounts, scopes and bolts from converted PU sniper rifles were put into storage, these are still available in large numbers in former USSR countries.
P.S. Why are M91 sniper rifles mentioned in the title? The Earliest soviet sniper rifles were build on the base of a Dragoon M91 rifle, after WWII they were considered as "non-standard" . Some collectors were lucky to find "ex-dragoon" "ex-snipers", that originally were drilled for Walther or GECO mounts in the very early 1930's