When he was aged seven, his family moved to Krasny, where his father – a land surveyor and his mother, a teacher, both of ethnic Russian extraction – came from.

In 1942, he was ordered to return to the Institute of Chemical Physics (which was evacuated to Kazan) by the Deputy People's Commissar for Defense, Yevgeny Schadenko.

For this success, he received the Hero of Socialist Labour award; several others followed in ensuing years, including for work on the first Soviet thermonuclear weapon.

[2][3] Remaining on good terms with Igor Kurchatov, Shchelkin's knowledge, experience, managerial and business sense led to his recommendation as the first scientific director and chief designer of the new "second installation" for development of nuclear weapons at NII-1011 (also becoming known as Chelyabinsk-70 (now the All-Russian Scientific Research Institute for Technical Physics (VNIITF)), where research and development began in 1955.

He was sometimes openly critical of directives, which upset first secretary Nikita Khrushchev, and he had a disputes with Efim Slavsky, the minister in charge of Ministry of Medium Machine Building which oversaw the nuclear programme.

[2][3] Shchelkin continued to travel between Moscow, KB-11 and the laboratories in the Urals, planning expansions to or closures of sites as necessary and recruiting new staff, but he retired from his directorship in 1960 because of increasing ill health – he had suffered frequent heart attacks in 1959.

[2] The rotating flame front in cylinders of detonating gas is known as the Shchelkin spiral and research continues into its usage in propulsion.