A brief history of, and a couple of SKS Sniper Rifles (picture heavy)

[Jimja]

The very first SKS Sniper rifles were made in Russia for trials in 1949, they used a mount very similar to the ms74 mount that was also tried on Mosin Nagant sniper rifles around the same time, also in 1949

It is interesting to note that at this time, in 1949, several modifications to the Mosin PU sniper rifle were also sent to trials, the "MS" model, made by factory #74 (Izhevsk) and SV-2 and SV-3 models, made by OKB-180. More information about these and some great photos have been published by Alexander Yuschenko in his "Model of 1891/30 Rifle and its Variations. History of Development, Production, Modifications and Use" book on pages 398-400

All of these trials 91/30's, as well as the two trials SKS rifles shown below, used the PU scope

This is what the trial SKS rifles looked like (note the very early 90 degree gas blocks on both of these):

Tula trial rifle:


Tula mounting bracket:



OKB-180 trial rifle (this is where the the designer of the SKS, Sergey Gavrilovich Simonov worked)


OKB-180 mounting bracket:



Here is a (google translate) link to an article published in Russia last summer, the author based the article on the proving grounds report.

https://translate.google.com/translate?sl=auto&tl=en&u=https%3A%2F%2Fkalashnikov.media%2Farticle%2Fweapons%2Fotchet-strelkovogo-poligona-sks-dlya-snaypera

A more detailed version of this report exists in the Russian military archives. Unfortunately the archives hold the copyright and do not allow the report in it's entirety be published online, but the information that the report contains can be made public. The most interesting information (to me at least) were the accuracy requirements requested by the military for the SKS sniper, as well as the actual proving grounds results. Special thanks to Alexander Yuschenko for help with details/translation


Here they are:

The Soviet military requested that the accuracy for the scoped SKS (the actual request was for a "semi auto sniper carbine") be at least:


8.5 cm group at 100 meters (3.35" at 109.36 yards)
3.5 cm best 50% of the group (1.38" best 50%)

25 cm group at 300 meters (9.84" at 328 yards)
10 cm best 50% of the group (3.94" best 50%)



The proving grounds report states that the test results were:

8.1 to 10.2 cm at 100 meters (3.19" to 4.02" at 109.36 yards)
3.8 to 4.5 cm for best 50% (1.50" to 1.77" best 50%)

27 to 33 cm at 300 meters (10.63" to 12.99" at 328 yards)
12 to 12.7 cm best 50% (4.72" to 5.00" best 50%)


The tests were done with 4 shot groups, this was the standard soviet test at the time (used for mosins, SVT40's, etc)
The Best 50% of the group means the best two shots. According to Russian Mosin and SKS manuals, if one shot was far away from the other three, it was to be ignored. In this case the best 50% would be the best 2 out of 3

It is also important to note that the Soviet ammunition at this time had fairly bad accuracy, this regular ammunition was used in these tests.

I think it's likely that the bad/low quality of Soviet ammunition had a noticeable impact on the proving ground test results.
There are wartime reports from factories saying that the ammo that they received had a 10cm (3.94" at 109 yards) spread in ideal conditions while the expected accuracy of the sniper rifles they were to produce was to be 8cm (3.15" at 109 yards)

The other problem that the report mentions was that the mounts were "not durable"


The trials were a failure, neither rifle was accepted, and no SKS sniper rifles were ever made......

[Jimja]

....until the 1990's, when the JNA (Jugoslovenska narodna armija), Yugoslav People's Army, modified around 200 (no real verifiable source behind this number) SKS rifles into Sniper/DMR configuration by taking the Zrak ON-2 Scope from the Zastava M69 Sniper rifle, re-camming it from the original 8mm Mauser to 7.62x39 and designing a sort of reverse-pu style mount with a new mounting bracket

Some of these ex-sniper Yugo sks's were imported, various sources I've read say that around 70-100 of these rifles were imported. None had mounts or optics (as far as I know), very few had bases, the majority were only drilled for them.

The majority of those were the Yugo M59/66 model, very, very few of the M59's were imported in this configuration.

Here are two complete Yugo SKS snipers, from my personal collection, an M59 and M59/66 (Yes, the GL on the 59/66 has been modified for California compliance)

[Jimja]

Here are some interesting details about these modifications. The eye relief of the Zrak On-2 scope is longer then that of the PU. Because of that, the Yugo M59 had extended rubber buttpads attached to make the length of pull better. There are a few M59 scopeless SKS snipers with this extended buttpad. No known ex-sniper or sniper M59/66's exist with it

Detailed photo:





Interestingly, in the Russian SKS sniper trials the PU scope was moved to the left side of the receiver, this offset allowed the rifle to be loaded using stripper clips. The JNA took a different approach, the scope itself was moved further back. This allowed for the rifle to be loaded with Yugo M67 ammo using the provided stripper clips. Here are some photos:









The base and mount is a very interesting design, it's like a very high, reverse style PU mount with a double thumb screw. Unlike the single PU thumb screw, the JNA added a second screw to lock and prevent the first screw from coming loose





Details of the Yugo base/mount

[Jimja]

The Yugo SKS base compared to the Soviet PU base





Soviet PU Mount on a Soviet PU base





Soviet PU mount on a Yugo SKS base, the PU mount is obviously reversed in this picture





History/comparison of the scopes and mounts. This shows an interesting evolution/adaptation of different design elements

Top: Zrak ON-2 scope in 8mm Mauser on a mount for the Zastava M69 Sniper Rifle
Middle: Russian PU scope in 7.62x54r on a mount for the PU Sniper Rifle
Bottom: Zrak ON-2 scope, converted to 7.62x39 on a mount for the SKS Sniper Rifle







This picture shows two Zrak ON-2 Scopes on their respective mounts.
Right: Zrak ON-2 in the original 8mm Mauser calibration in a mount for the Zastava M69 Sniper rifle
Left: Zrak ON-2 converted to 7.62x39 in a mount for the SKS Sniper rifle





Zrak ON-2 with turrets calibrated for 8mm Mauser





Zrak ON-2 with replaced turrets, calibrated for 7.62x39





The reticle for both of these remained unchanged, it's a reverse-style POSP Warsaw pact rangefinding reticle

[Jimja]

How do they shoot?

Not great, like an SKS, roughly 3-4 moa on the M59/66 (I should mention this is with cheap/surplus ammo using iron sights). The scoped M59/66 isn't that comfortable to shoot as the scope sits too far back. The M59 is a lot better with the added buttpad. The Soviet SKS test rifles were probably better in this respect

Looking at the first couple of photos of the Russian trial SKS, I can't help but think that a cheekriser should have been added when these were converted. Obviously a lot of work went into the design and manufacture of a very limited amount of these bases and mounts. An extended rubber buttpad was added, why not a quick/easy cheekriser?.

It is possible that these rifles had them, but that they were removable, so when the rifle was packed for export it was the rifle only, no cheekriser, scope or mount included


This Sunday I did an unofficial test using a few different kinds of ammunition at 100 yards. For groups, the M59 was shot since it has much better ergonomics due to the extended buttpad.
The scope mount had a problem coming loose and had to be tightened a couple of times, it's definitely not nearly as solid as the PU sniper mount.
Out of the different types of ammo used, the Geco target was by far the best out of the bunch (by a big margin)






This is the best group, Geco brass cased target ammo at 100 yards. Using the soviet method of testing (ignoring the flyer) this gives it a roughly 1.5" group with a 0.50" best 50%. Surprisingly good for an SKS!
By this criteria the rifle would have passed the soviet requirement and would be fit for service!
Although, to be fair, if I used the Tulammo/Wolf results, the rifle wouldn't pass - this brings me back to the point about the quality of 1949 soviet ammunition used by the proving grounds





Of course this was the best group, others were not as good, some were pretty bad. Ammo made a huge difference, Tulamo was (not surprisingly) pretty bad
I'll do this test again at some point in the future, with the M59/66 as well, I'll also try the Yugo surplus M67 ammo out of curiosity


Update


A friend recently sent me a scanned copy of a Slovenian ON-2 Scope Manual. The manual, which unfortunately is undated, is fascinating as it specifically mentions and shows the ON-2 scope modified for use on an M59/66 Yugo SKS sniper rifle. This is the only official document (that I'm aware of at this point) that shows these SKS sniper modifications. Here are some photos and an English translation I did for the parts mentioning the SKS



Cover and translation:

Optical Sight ON-2

(Description, operation and maintenance)





Index Page and translation:

1.1.3.

Two types of mounts allow the optical sight, with the appropriate division on the distance drum, to be used on the special sniper rifle 7.9 mm M69 and the semi-automatic rifle 7.62 mm M59/66





Page showing the M59/66 (and the M69) and translation:

4.1.2.

Mounting on a semi-automatic rifle 7.62 mm M59/66

The optical sight ON-2 with the mount is placed so that the spherical bearing of the body of the carrier 3 (si 3-4) rests on the spherical spout 8, and the prismatic spout under the screw 5 on the corresponding prismatic recess in the bracket 7

By turning the tightening screw 9 in a clockwise direction, the fastening of the brackets with the ON-2 sight for the rifle is performed, the tightening must not be performed with excessive force.





Closeup of the M59/66 diagram and translation:

Sl. 3-4

Mount for the semi-automatic rifle 7.62 mm M59/66





There is a lot of speculation as to what was the point of scoping an SKS, the 7.62x39 M67 Yugo round falls like a brick at distance. Most likely it was meant as a force multiplier, I will write about this later and update this post

I hope you found this interesting!

[Jimja]

Slightly off topic:

A little bit of Yugo/Soviet history that I find fascinating:

1947 - Tito gets PU sniper rifles from Stalin (mostly, if not all, Izhevsk made)
1948 - Tito and Stalin decide they no longer get along https://en.wikipedia.org/wiki/Tito–Stalin_split

[Syntax Error]

Cool photos, you got a light box now.

[frahuang]

Good stuff right here.

[Spartan301]

Yugo M59/66A1

Very cool, great pics OP!

Just by chance, I picked up a Yugo M59/66A1 Ceremonial SKS today.

Not as cool as your snipers, but I think kinda rare.

2E84C4B9-4245-40ED-A2D3-4A3B4869EC67_4_5005_c.jpg
Slovakian Honor Guard.


Thanks for sharing!

Spartan301

[DBA]

Very cool thank you for sharing. I will tune back in to read about groupings.

[Rogerbutthead]

So I should not have laughed at the SKS sniper rifles in "Siege of Firebase Gloria" - ?

[Lebaneseblonde]

Love it

[echo1]

Great stuff. Factory engineering which validates what most folks have said about SKS & scopes. Still getting the same results. PAX

[metalcruncher]

Nice, informative read. Thanks

[Bukowski]

Great write up and photos, thanks.