It shouldn’t be cached at all unless there’s also a Cache-Control
or Expires
header returned by the web server. According to RFC 2616, section 10.3.3 302 Found
The requested resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. This response is only cacheable if indicated by a Cache-Control or Expires header field.