I'm not sure why you chose those numbers. Yes, if nothing on your local network is connected to the internet, there is no potential problem. However, the reason we normally use reserved addresses for local networks is in case of any potential errors in configuration, which could possibly cause other people on the net some grief.
Code:
Private Address Space
The Internet Assigned Numbers Authority (IANA) has
reserved the following three blocks of the IP address
space for private internets (local networks):
10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255
For small lan's most people choose the 192.168.0.0 range.