You can simply repack various compressed archives when you extract the content of the original archive and compress it in a new one.
Convert 7-ZIP compressed 7z archive to Compressed file from a multi-volume archive (part 1).
We have found 6 software records in our database eligible for .7z to .001 file format conversion.
Microsoft Windows software - convert 7z to 001 on Windows
One of the oldest and most popular shareware file archiver and data compression utility
Convert from 7z file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned 7z to 001. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Popular open source file archiver with a high compression ratio
A free open source archive utility
Apple macOS / Mac OS X software - convert 7z to 001 on OS X
A backup and archive utility
Mac version of the popular utility
Linux/Unix software - convert 7z to 001 on Linux
A Linux application used as frontend for popular compression tools