The calculated distance (air line) between Volgograd and Chyorny Yar is approximately 87 miles respectively 139 kilometers.
By car or train, the actual journey to Chyorny Yar is certainly longer, as only the direct route (as the crow flies) between Volgograd and Chyorny Yar has been calculated here.
Air line (approximately)
139 kilometers
75 nautical miles