Swiss K31 as a sniper rifle

cuirc

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  • Nov 8, 2023
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    Poughkeepsie n. y.
    I have a Swiss K31 that shoots very well so much that I would like to convert it to the extent possible as a sniper rifle. But I don't want to put any modern scope that is readily available on it. I would like to keep it a close to what an original would be. Does anyone know what is the best scope in this situation. I understand the the Valdada is as close as any but new ones are as much as a Nightforce. Problem is I have drawn a blank on locating a vintage scope feedback from anyone with a source would be appreciated.
     
    Hi cuirc,

    Your wish is very well understandable. Yes. Thats what quite a lot of K31-owners think. (included me :) ) Not all are courageous enough to point that out publicly. The are since a long time many different K31-Sniper-resp. Targetrifle-conversions known. Some examples in the pics below.

    The technical aspects depend particularly on the time or period to which your K31 should match then. For example 1950, 1970, 1990, perhaps ?
    To the scopes yourself: As far as I know - there are just 3 old scope-types which have actually been installed here in the Swiss Army - including test-examples and serial-rifles. The K31/42, K31/43 and the K31/55 resp. Zfk 55. The most comfortable of them is in general opinion the 3,5x of the Zfk55. But that is probably not easy to find nowadays. Unfortunately, I don't have a source for that now.. .

    Some 100 K31 around 1949 with probably 4x-Kahles-Scopes, were first sent to Nicaragua. But they reached then Israel as far as we know. Pic down. I remember there was an article to that subject, some years ago. A journalist could find one of the gunsmiths from then by Hämmerli. This said that he is not really sure with that Kahles-Scopes.. .

    The more comfortable 6x scopes only appeared - generally - in significant numbers in the 1970s. Maybe you can find an older Schmidtund-Bender or Pecar with 4x-power.

    My Zfk 84 (f for fictive)-Conversion with his 10x-Zf is too modern in that case.. .

    What is then a suitable scope for you, cuirc ? :) :unsure: Which reticle and which magnification, f.e. ?

    Just my 2 cents :)
     

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    This is what the original sniper rifles look like on the right half of this photo. There is one other export version that I believe wound up in Israel.

    1725373077078.png


    This is the variant that found its way to Israel. Optic is akin to the ZF-39 found on many K98k sniper rifles of WWII.

    1725373103131.png



    The K31/42, K31/43, and K31/44 all have a dovetail machined into the left side of the receiver for the optic to directly attach. Some of the early (first 120 or so) 31/42's were even welded after being press-fit dovetailed. Obviously good luck finding a suitable optic for that. Likely doesn't exist. The ZFK 55 has scope mount bosses machined into the receiver integrally.

    The Israeli variant would be the easiest to clone if that's what you're going for. I believe some German scopes were tried in the 1930's as prototype experiments and the Swiss weren't very impressed with the durability and repeatability of the mounting systems (hence the welding of the scope tube to the receiver in the K31/42's). Those German scopes are all 26.5mm main tubes and finding rings might be a problem. It might be possible to make some K98k side-mount solutions fit on the K31 but you may also run into problems with the top-eject nature of the action.

    The "easy button" IMO is a Weaver K4 or K6 with one of the St. Marie clamp style mounts. I suppose if a guy could find appropriate sized rings a ZF39 could be mounted to one of those as well, or maybe even some of the 7/8" tube optics of the era.
     
    Well I just won an ebay bid on a IOR Valdada 4-14x50mm scope being a European scope, as "I understand it it might have been used on the K31 for sniper purposes; if not I at least got something a lot closer to correct than a Leopold (no offense to Leopold). I think this will make a nice pair now I need to find a good mount. The rifle it self shoots very well as the other one I have with dioptic sights.
     
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    Hi cuirc,

    Your wish is very well understandable. Yes. Thats what quite a lot of K31-owners think. (included me :) ) Not all are courageous enough to point that out publicly. The are since a long time many different K31-Sniper-resp. Targetrifle-conversions known. Some examples in the pics below.

    The technical aspects depend particularly on the time or period to which your K31 should match then. For example 1950, 1970, 1990, perhaps ?
    To the scopes yourself: As far as I know - there are just 3 old scope-types which have actually been installed here in the Swiss Army - including test-examples and serial-rifles. The K31/42, K31/43 and the K31/55 resp. Zfk 55. The most comfortable of them is in general opinion the 3,5x of the Zfk55. But that is probably not easy to find nowadays. Unfortunately, I don't have a source for that now.. .

    Some 100 K31 around 1949 with probably 4x-Kahles-Scopes, were first sent to Nicaragua. But they reached then Israel as far as we know. Pic down. I remember there was an article to that subject, some years ago. A journalist could find one of the gunsmiths from then by Hämmerli. This said that he is not really sure with that Kahles-Scopes.. .

    The more comfortable 6x scopes only appeared - generally - in significant numbers in the 1970s. Maybe you can find an older Schmidtund-Bender or Pecar with 4x-power.

    My Zfk 84 (f for fictive)-Conversion with his 10x-Zf is too modern in that case.. .

    What is then a suitable scope for you, cuirc ? :) :unsure: Which reticle and which magnification, f.e. ?

    Just my 2 cents :)
    WELL I PAID $650 FOR THIS AND I THINK AT LEAST IT IS AN OLD SCOPE THAT CONCEIVABLY COULD HAVE BEEN USED. THE POWER RANGE FITS IN YOUR RANGE: IT WILL DO. THE MOUNT IS EASY TO ADDRESS WITH A RAIL BUT IT NEEDS TO BE OFFSET FOR THE EJECTION. A BIGGER QUESTION FOR ME IS THE BI POD. AMY IDEA WHERE TO FIND SOMETHING LIKE THAT. I WISH I KEPT THE CARD FOR A GUN STORE I like IN LAZURN. (sorry for caps). it is in one of the side streets near the lake if you are familiar the area.
     
    WELL I PAID $650 FOR THIS AND I THINK AT LEAST IT IS AN OLD SCOPE THAT CONCEIVABLY COULD HAVE BEEN USED. THE POWER RANGE FITS IN YOUR RANGE: IT WILL DO. THE MOUNT IS EASY TO ADDRESS WITH A RAIL BUT IT NEEDS TO BE OFFSET FOR THE EJECTION. A BIGGER QUESTION FOR ME IS THE BI POD. AnY IDEA WHERE TO FIND SOMETHING LIKE THAT. I WISH I KEPT THE CARD FOR A GUN STORE I like IN LAZURN. (sorry for caps). it is in one of the side streets near the lake if you are familiar with the area.
     
    I have two of these rifles, they shoot great. One of them I put dioptic sights on (that I picked up in Switzerland), for iron sights they are incredible. The second rifle, I used the military sights on with the future intention of putting a scope on. I finally moved on that. One hangup I had, was I didn't like the one screw mount I saw around and was unaware of anything else. Now that I have this scope, which I bought by "accident" meaning I put the value of the scope at over $1000 and wasn't going to pay that, so I put a bid on it almost for laughs and what do you know but I won. Now I will have to put this project in the higher priority pile and get a mount which will require some research on my part. It looks like it will have to be mounted offset to accommodate the top ejection. Its amazing with these rifles. a good while ago, I bought the two for around $300 each now I see prices on them of $1200.
     
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    Well I just won an ebay bid on a IOR Valdada 4-14x50mm scope being a European scope, as "I understand it it might have been used on the K31 for sniper purposes; if not I at least got something a lot closer to correct than a Leopold (no offense to Leopold). I think this will make a nice pair now I need to find a good mount. The rifle it self shoots very well as the other one I have with dioptic sights.
    That sounds good.. The IOR Valdada-scope is an older company, true.. .

    What about the reticle in it ? I'm in a hurry, more later.. . :);)
     
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    That sounds good.. The IOR Valdada-scope is an older company, true.. .

    What about the reticle in it ? I'm in a hurry, more later.. . :);)
    I think you said you had a mount what kind is it I remember they had one that only needed one screw I think I want something more substantial. I think it would need several mounting points on the left side and perhaps a rail that puts it offset for the top extraction.
     
    I put a scope on my K31 with one of the St. Marie clamp on mounts. I enjoyed it for a while but eventually began to despise the aesthetics of a beautiful classic rifle with what was clearly not period correct stuff hanging on it.
    With the exception of difficult to see targets, the scope barely increased my hit percentage also.
    I took it off, sold it, and if I do anything with it in the future it will be diopter sights.
     
    Hi cuirc,

    Your wish is very well understandable. Yes. Thats what quite a lot of K31-owners think. (included me :) ) Not all are courageous enough to point that out publicly. The are since a long time many different K31-Sniper-resp. Targetrifle-conversions known. Some examples in the pics below.

    The technical aspects depend particularly on the time or period to which your K31 should match then. For example 1950, 1970, 1990, perhaps ?
    To the scopes yourself: As far as I know - there are just 3 old scope-types which have actually been installed here in the Swiss Army - including test-examples and serial-rifles. The K31/42, K31/43 and the K31/55 resp. Zfk 55. The most comfortable of them is in general opinion the 3,5x of the Zfk55. But that is probably not easy to find nowadays. Unfortunately, I don't have a source for that now.. .

    Some 100 K31 around 1949 with probably 4x-Kahles-Scopes, were first sent to Nicaragua. But they reached then Israel as far as we know. Pic down. I remember there was an article to that subject, some years ago. A journalist could find one of the gunsmiths from then by Hämmerli. This said that he is not really sure with that Kahles-Scopes.. .

    The more comfortable 6x scopes only appeared - generally - in significant numbers in the 1970s. Maybe you can find an older Schmidtund-Bender or Pecar with 4x-power.

    My Zfk 84 (f for fictive)-Conversion with his 10x-Zf is too modern in that case.. .

    What is then a suitable scope for you, cuirc ? :) :unsure: Which reticle and which magnification, f.e. ?

    Just my 2 cents :)
    This is what the original sniper rifles look like on the right half of this photo. There is one other export version that I believe wound up in Israel.

    View attachment 8493518

    This is the variant that found its way to Israel. Optic is akin to the ZF-39 found on many K98k sniper rifles of WWII.

    View attachment 8493519


    The K31/42, K31/43, and K31/44 all have a dovetail machined into the left side of the receiver for the optic to directly attach. Some of the early (first 120 or so) 31/42's were even welded after being press-fit dovetailed. Obviously good luck finding a suitable optic for that. Likely doesn't exist. The ZFK 55 has scope mount bosses machined into the receiver integrally.

    The Israeli variant would be the easiest to clone if that's what you're going for. I believe some German scopes were tried in the 1930's as prototype experiments and the Swiss weren't very impressed with the durability and repeatability of the mounting systems (hence the welding of the scope tube to the receiver in the K31/42's). Those German scopes are all 26.5mm main tubes and finding rings might be a problem. It might be possible to make some K98k side-mount solutions fit on the K31 but you may also run into problems with the top-eject nature of the action.

    The "easy button" IMO is a Weaver K4 or K6 with one of the St. Marie clamp style mounts. I suppose if a guy could find appropriate sized rings a ZF39 could be mounted to one of those as well, or maybe even some of the 7/8" tube optics of the era.
    Hi:
    I have two K31s one has dioptic sights ,the other just the military sights I would like to put a scope and a bipod on the second one. Purely by luck I won a bid on Ebay for a Valdada 4-14 50mm scope with a 30mm tube. I would like to use that, keeping it European and possibly closer to what original would be. Recognizing that it is a top ejector (which means I need to grow neck) i see some difficulties with he scope. I am also at loss to the best way to mount a bipod I suppose it could be fastened to the wood for arm but I don't think that would be very suitable
     
    Hi cuirc,

    I was unfortunately absent for a couple of days. Therefore this "silence, only.. .

    My Zfk 84 (f) carries since 2005 the Richner-Mount :) To my complete satisfaction. So simply to install, participation of a gunsmith is not necessary, usually. See the pics down. Please.

    Schmidt-Rubin Zfk 84 (f) von links gesehen.jpg

    Respectively here, too :) https://www.snipershide.com/shooting/threads/scope-mount-for-swiss-k31-rifle.7227630/#post-11729720

    My Zfk carries no bipod.. . The centered mount is better suited for a scope like your Valdada, the side-mount reduces the scope-size, say our Long-Range-shooters here.

    More later
    BR
     

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    Here we are :) with the link for Richner.ch resp. now the Munitionsdepot.ch:
    The link for Gunfactory.ch: https://www.gunfactory.ch/optic/zf_montagen_k31.htm


    To the reticle: the "typical" reticle for the earlier K31 are the so-called No. 1-Absehen, f.e. the Zfk 55. The post and wire-reticle. See 1th line, left.

    And down there an example for the Zfk 55-Reticle, too.

    In my Zfk-Project I tried to stay as near as possible in this period, tecnical seen.. . But with an better scope and reticle, in the end, of course. To my luck, then - 2005/2006 - Pecar was still producing. Their "Champion"-Series with the Reticle 1 was clearly the most suitable scope for my purpose. The last pic shows their Reticle 1, sufficient similar to the Zfk 55 Kern-Reticle.





    Zeiss-Reticle-Absehen-Overview Übersicht.jpg
     

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    1728942693583.png

    Is this the clamp on mount you are referring to if so I will buy one. I have the stocks of both guns sanded down to 800 grit wetting the wood as i went along They have come out pretty good considering what they looked like before I stared. I am going to finish them a litle darker than the original. using min wax gun stock stain darkened 20% by volume with Min wax walnut. I tested it ad it looks pretty good. Swiss Products has this mount and a bipod also. If this is not the mount you mention and know where to find it I will take a look. now that I am committed to this job.


    Thanks for oall the help you have given me.
     
    View attachment 8524259
    Is this the clamp on mount you are referring to if so I will buy one. I have the stocks of both guns sanded down to 800 grit wetting the wood as i went along They have come out pretty good considering what they looked like before I stared. I am going to finish them a litle darker than the original. using min wax gun stock stain darkened 20% by volume with Min wax walnut. I tested it ad it looks pretty good. Swiss Products has this mount and a bipod also. If this is not the mount you mention and know where to find it I will take a look. now that I am committed to this job.


    Thanks for oall the help you have given me.

    Hi.

    No, that is not this mount-type, cuirc.. . Unfortunately. This is a clamp-mount probably on a K11, not on a K31.. .

    I can't recommend this clamp-mounts, as i mentioned earlier. IMHO it's in every case the better solution mounting a riflescope with an centered mount. In general. The development of K 31-mounts resulted in the centered mount with a rail, after several clamp-mounts. Pics down. That says to me that there was a need for better mounts. Today exist these better mounts. See here the details: https://mittelkaliber.ch/karabiner-31/
    Consider the aiming-position of your head, the Richner-Mount is a bit high. A headbutt noticeably improves then your comfort. If possible, try out one or several rail-mounts before the purchase. And I can eject the case with not so much muscle-power during half a afternoon ;):p

    Pics: Headbutt-example, rail-mount-K31 from behind, headposition with dioptre, old Andretto-Mount, an early centered mount, Zfk 84 (f)-butt


    There are several such mounts around - unfortunately I don't know the world of your gunshops there in N.Y. at all - probably New York ? :) I would get in contact with the two swiss companies, by Email f.e., in your place. And if that doesn't help somebody in your environment can probably help. Switzerland exports their good products usually in great quantities often - mainly - in the USA.. :sneaky::) Good success.

    Maybe your project needs a bit more time than originally planned, cuirc? :unsure: ;)

    Your "woodwork" sounds really good ! That's something I can't do myself.. . Respect. Such a work I only can admire. And hope that in such a case my old friend has a bit time left to do such a refinement for me.. .

    Best regards
     

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    You matched the type of targets, the distance with the scope-model and this reticle already, I suppose.. ?

    The European Reticle 1, see above - in German das Absehen 1 - is good usable on such targetpapers as after the text, according to my experience.

    This combinations bring the K31-accuracy to the target, in the end. Even when it's getting dark.. .Therefore comes my "contribution" to that part of the chaptre sight.
    You use probably a Crosshair-version in your scope, not ? A more american reticle-type. With good weather it's okay, but it should stay good.. :unsure:


    Well, just my 2 cents 🙃🧐
     

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    thank you
    Since found a suitable mount for the Valdada scope I bought I decided to refinish both rifles. I sanded them down and mixed some stain to darken the wood a little. I just put the first coat of oil on the stocks. I will probably piut 5 or 6 coats on. The wood cleaned up very well I went up in sandpaper to 2000 grit so the stocks are extremely smooth and look pretty good. When I finish and have the scope mounted I will post pictures.
    I have been thinking that since the action is, for a bolt action very fast cycling it might make a nice ELR rifle in a caliber like 300 PRC. So
    i am considering buying another for conversion as described above. The only problem to solve is how to improve the stock to complement what the caliber conversion to I think, might be a fast accurate ELR.
     
    Since found a suitable mount for the Valdada scope I bought I decided to refinish both rifles. I sanded them down and mixed some stain to darken the wood a little. I just put the first coat of oil on the stocks. I will probably piut 5 or 6 coats on. The wood cleaned up very well I went up in sandpaper to 2000 grit so the stocks are extremely smooth and look pretty good. When I finish and have the scope mounted I will post pictures.
    I have been thinking that since the action is, for a bolt action very fast cycling it might make a nice ELR rifle in a caliber like 300 PRC. So
    i am considering buying another for conversion as described above. The only problem to solve is how to improve the stock to complement what the caliber conversion to I think, might be a fast accurate ELR.

    I see, our K31 have an inspiring effect on you, cuirc :giggle:😉

    That's fine ! Just go ahead.
     
    Just put the 5th coat on will do a sew more I started using oooo steel wool to break the finish. The rings that came with the mount sit perfectly. I didn't do bad on the scope either they sll on Planet optic for around 3k and I paid 600! Probably finish by middle of the next week then to sight it in
     
    Just put the 5th coat on will do a sew more I started using oooo steel wool to break the finish. The rings that came with the mount sit perfectly. I didn't do bad on the scope either they sll on Planet optic for around 3k and I paid 600! Probably finish by middle of the next week then to sight it in
    That sounds good.. Which ammo, please ?
     
    Hmmm.. 2 Cases with each 60 rounds or each 480 rounds ? The 7,5 mm Swiss-Reloading is always a interesting subject .. .

    Supposing it's a Match-load, what bullet-weight may it be, then ? :unsure::)
     

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    Held one up by a 308 and a 3006 I would guess 175 to 180 grain

    :)🙃 This plastic bag with 7,5 x 55 mm Swiss-Reloads was only a spontaneuous example for such ammo.. Occasionally recently detected.. . A fitting pic, as I thought.. .

    My question referred to the Swiss Army-packages, simply said. So-called "Gaschons" in Swiss Dialect. One size holds 60 rounds, the large on 480.

    Then you plan another 175-180 grs HPBT-Match-Round, I see.. . Maybe a Sierra-Matchking-Bullet.. . Some 185 and 190 gr-recipes I saw earlier..
     
    :)🙃 This plastic bag with 7,5 x 55 mm Swiss-Reloads was only a spontaneuous example for such ammo.. Occasionally recently detected.. . A fitting pic, as I thought.. .

    My question referred to the Swiss Army-packages, simply said. So-called "Gaschons" in Swiss Dialect. One size holds 60 rounds, the large on 480.

    Then you plan another 175-180 grs HPBT-Match-Round, I see.. . Maybe a Sierra-Matchking-Bullet.. . Some 185 and 190 gr-recipes I saw earlier..
    Yes these are sierra matchking BTHP 175 group will probable get to the range early next week
    I am still working on a load for my 338 LM
    I also, in the near future have 4 more to work up a .223, .243, 6.5 PRC and a 300 PRC all on Remington 40-X actions
    I am hoping the 300 will workout for ELR
     
    My question refers primarly to the production-date because of the rather different production-details by the GP 11.

    The newer one from 2016 onwards have to be "reconstructed" with quite a lot of effort, time and new materials.. .

    And the newer one from 2026-2018 caused problems in our old repeaters.. :rolleyes: