North Korea can unbalance the rocket game.
The former Soviet doctrine and the basis of Russian modern ground doctrine is the artillery, mainly the rocket artillery. The Russian MLRS, including the BM21, Uragan, and Smerchs, play a central role on their battlefield.
The 122mm Grad rockets used by the BM21 are key to the saturation strategy and cost around $600-800 for Russia, which is less than the cost of a conventional 155mm shell paid by Western countries.
The Russian had more than 3,000 BM21 launchers before the Ukrainian invasion.
During the first months of the war, massive barrages of Grads were witnessed on Ukrainian positions.
This Russian supremacy was challenged when Ukraine began to receive supplies from Polish Mesko, Slovakian MSM, Czech Excalibur, Romarm from Romania, Serbian Edepro, and mainly four Bulgarian companies that manufacture a variety of 122mm rockets.
These companies produce the latest generation of Grad rockets, capable of reaching 40km, which is the same range as the more modern Russian Tornado-G rockets.
In the midst of this Grad battle, Pakistan signed a contract to supply Ukraine with 200,000 rockets and has already delivered over 140,000 by April/23.
The Pak rockets supplied to Ukraine are the KRL-122, with a range of 40km. This large delivery was oxygen for the Ukrainian BM21.
The allies have established a long-range Grad supply network, challenging Russian supremacy in this field. Although there are no official numbers, we can estimate that these companies, along with support from Pakistan, can deliver approximately 7,000-14,000 of these rockets monthly to Ukrainian forces, with most of them having a 40km range.
For Russia, the issue is that the 9M521 rockets, capable of reaching 40km, only started being produced after 2019, and as any ammunition, it takes time to ramp up production.
About the Uragans and Smerchs, the NVO Splav is investing to raise the production and refurbishing old rockets, but these launchers are heavier and requires more logistics. The key system for the saturation keep being the grads.
Even Belarus, one of Russia's usual allies, began producing their own 40km Grad rockets only last year.
Russia has an immense network of countries that can manufacture and supply 122mm rockets, such as Sudan, Belarus, and central Asian countries. However, all of these countries only manufacture the 20km range Grad rockets, and at this game, range does matter!
The only countries able to make a significant difference on Russian side, at a large scale are Iran and North Korea, as they massively manufacture long-range Grad rockets.
Iran has the Arash 4 rocket, which is compatible with the BM21 launchers. It could potentially alleviate Russia's problems. However, there may be a sensitive situation between Russia and Iran about Grads.
Like 2 decades ago, the Russians refused to transfer the technology for Iran to manufacture their own version of the BM21.
Despite the refuse, the Iranians developed their systems independently, and there might be some individuals in Iran who are not too happy about sending a considerable amount of their rockets to Russia.
Left North Korea, which surely has a large number of these Grads, able to unbalance the rocket artillery game, not only with Grads, but also with other bigger calibers like 200-300mm in large scale.
The potential impact of possible deliveries from North Korea to Russia has the potential to completely unbalance the artillery game in every level.