You need to learn Russian. Seriously

Or at least learn to use some online translator effectively

Then you can search Runet (Russian language Internet segment) for all kinds of stuff, from tech manuals to patents and textbooks for weapon designers.

For serachning in Russian I recommend Yandex www.ya.ru search engine 

I actually found out about that book just before making this post and really interested before but unfortunately it would be really hard to get it legitimately let alone shipping it to my country. And i can't find any info whether they sold in pdf format or not either.

But i found some useful information of russian cartridges on that site so i guess that counts. thanks anyway!

roguetechie said:

I'll do my best to point you in helpful directions. Also if you join weaponsguild.com and make enough posts to access the full pattern room subforum there's untold riches available there for the taking.

that would be a treasure for gun designer like me!. I'll be sure to check it out.

I actually able to learn a lot about gun designs by reading gun pdf manuals because most of the times they have useful disassembly instruction and pictures of exploded views showing the internal mechanism.

i'm currently in progress of designing a large caliber machine gun, possibly 12.7 cal or higher
so like i said in my original post, i'm in a journey of finding some technical infos of large caliber russian made guns like the dishka, kpv, nsv, and etc.

I know about the older design of the dishka that uses rotary feed sprocket, but i'm more interested in the different  version of the dshk which uses different feed mechanism.

Also if possible i would like to learn more about the mechanism of russian autocannon like the 2A42, KPV 14.5 and the GSh series.

There's also the russian military forums. i forgot which one, but i think it's more focused in aviations. did you perhaps know any russian patent websites out there?

I have a full set of AK blueprints. PM me.

Russian patent system is working together with Euro patent systems, so many non-classified patents issued in Russia after 1991 and until present time can be found through the European patent office website: https://worldwide.espacenet.com/advancedSearch?locale=en_EP

You need to use prefix RU for patent publication No, and CPC / IPC class F41 for weapons. Example: all weapons related Russian patents for 2020:

search criteria:

https://worldwide.espacenet.com/searchResults?submitted=true&locale=en_EP&DB=EPODOC&ST=advanced&TI=&AB=&PN=RU&AP=&PR=&PD=2020&PA=&IN=&CPC=F41&IC=&Submit=Search

Results:

And of cause you can narrow your search results by class or description

I agree. You can try to translate into Russian using Google translator. But to be honest, I have been using another online service to translate hawaiian to english for my travel blog for a long time. I like the reliability and ease of use of this platform, as well as the comprehensive functionality. Usually, I use machine translation based on artificial intelligence to translate simple texts. So I think it's a great fit to solve your problem.