Most of the cars obtained in the Rb467 million (US$7 million) transaction were produced by Altaivagon OJSC and RM Rail Ruzhimmash and are both bought-to-own and leased units.
The cars are now part of a 11,000 train vehicle fleet that is managed by Mechel's transport operator Mecheltrans.
More than 1,000 gondola cars are still to come in 2019, the company confirmed.
CEO Alexey Lebedev said the upgrade comes after more than 150,000 cars were scrapped over the last four years - about a quarter of its fleet volume - due to expired life.
"The shortage in all-purpose vehicle transport segment is still being felt," he added. "As such, in order to improve the situation with transporting Mechel Group's coal products, we intend to dramatically expand our fleet."
Mechel is currently in active discussions with wagonbuilders as well as leasing companies for that effort.