Chertok makes the really interesting point that although the cosmonaut program was run by the Air Force, the rocket program (to begin with) was run by the artillery arm and a lot of the industrial contractors were either used to building guns, or else automotive or even navy* stuff.
It was only when the rival projects with Chelomey's OKB 52 started up that the aviation industry got involved, and the reason why OKB 52 got on so quickly was that their contractors knew what they were doing. Chertok mentions the first time he got to have a look at an UR500, which was built by the Moscow-suburb aircraft plant where he did his apprenticeship in the 1920s - he was amazed by how good the fit and finish was compared to his own lot's R7 Semyorka, and by implication, how many of the failures OKB 1 sweated blood over were probably down to manufacturing quality control.
*Fire-control, not shipbuilding, but still...