Article is paywalled, https://archive.md/Du5yG

In other words, Russia is losing around 320 tank and artillery cannon barrels a month and producing only 20. The Russian engineering industry lacks the skills to build rotary forges; in fact, the world market is dominated by a single Austrian company, GFM. Russia is unlikely to acquire more forges and increase its production rate, and neither North Korea nor Iran have significant stockpiles of suitable replacement barrels. Only a decision by China to provide barrels from its own stockpiles could stave off Russia’s barrel crisis.