West Midlands Police officers arrested five people on suspicion of possession of firearms after the raid in Small Heath on Friday, July 16.
As well as a sub-machine gun, a shotgun and two pistols were found by officers, while a sawn-off shotgun was recovered in Ladywood.
The weapons will now be examined by forensics while enquiries continue.
Off the five people arrested, three have been released pending further investigation and two remain in custody.
A spokesman for West Midlands Police said: "Our priority is to protect members of our communities from people who carry weapons or commit crime."
Anyone with information about gun crime is asked to call West Midlands Police on 101, or Crimestoppers anonymously on 0800 555111.