Banning the IP range of a Troll

[mark350]

Hello,

I am having a problem with a troll on our website... I hope someone on here can help me...

We keep banning this person from our site (ban his IP address), however, he uses proxy data to quickly obtain a new IP and he'll simply re-register. So I decided to try something, however, I don't know if it's correct.

I've saved some of this person's IP address:
99.130.166.131
99.162.51.163
99.162.60.125
99.162.60.125
99.130.160.76
99.172.129.159
99.172.129.159
99.162.51.127
99.1.97.125

I went to whois.sc and got this information:
NetRange: 99.0.0.0 - 99.55.255.255

I then added this code to my .htaccess

order allow,deny
deny from 99.0.0.0
deny from 99.55.255.255
allow from all

Is this correct, or will I be banning the entire state of Chicago or something? Do you have any better suggestions on how to handle this guy?

** Currently, I am using this code:

order allow,deny
deny from 99.
allow from all

Thanks in advance for any help.