Probably a Copyright Issue.
That is probably why they didn't use Black Talon.
All in all I was impressed with the whole cleaning your weapon sub-plot or message. I don't get the feeling the show is anti gun because on more than one occassion they talk about or show Emily Proctor's character shooting or talking about shooting in a recreational sense.
In their line of work chances are they will deal with guns being used as implements of murder and they have to show this in the show. For them to also show a character who actually likes guns is a pretty good thing.
IMHO, and we all know what that is worth, just slightly more than a politicians.
Chris.