In August 1977, Boock constructed a rocket launcher called the Stalin Organ, which was capable of firing primitive missiles. He trained the weapon on the offices of the Federal Prosecuter. The launcher didn't work, and Boock claimed that he had a change of heart at the last minute and deliberately sabotaged the weapon himself.
In September 1977, Boock was involved in the kidnap-murder of Hanns-Martin Schleyer, and was one the RAF kidnappers who opened fire on Schleyer's car.
Boock distanced himself from the RAF in 1980. However in 1981 he was arrested in Hamburg. He played down his role within the RAF, though was sentenced to life imprisonment terms for his involvement in the Ponto and Schleyer murders. In 1992 he admitted his full involvement in certain RAF activities, such as the Schleyer murder.