I want to redirection from 302 to 301 through irule

So as per the irule, when user types the URL in the browser will he get the 301 response?

yes. what nathan is asking is why you redirect to the exact same url.

// config

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm virtual bar
ltm virtual bar {
    destination 172.28.24.10:80
    ip-protocol tcp
    mask 255.255.255.255
    profiles {
        http { }
        tcp { }
    }
    rules {
        qux
    }
    source 0.0.0.0/0
    vs-index 65
}
root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm rule qux
ltm rule qux {
    when HTTP_REQUEST {
  HTTP::respond 301 "Location" "http://[HTTP::host][HTTP::uri]"
}
}

// test

[root@ve11a:Active:In Sync] config  curl -I http://172.28.24.10/something
HTTP/1.0 301 Moved Permanently
Location: http://172.28.24.10/something
Server: BigIP
Connection: Keep-Alive
Content-Length: 0