G'Day tickmike,
The subnet will give you 5 usable not 6. One of the IP's will be set for the Gateway and is usually the second to last IP ie: *.*.189.49/29 which gives you *.*.189.49 - 55, however 54 becomes the GW, and because only the one IP is used then the GW subnet becomes .255. All the others are used on the network and need to know where the Gateway is, so therefore they need the .248.
Hope this helps.
-Azzaka