Many of the gun blogs are powered by wordpress. The latest version has just come out. This release was cooking for over 6 months!
Be careful when upgrading and make sure you have a backup of both the files and the database.
I messed up the upgrade on my blog (The Firearm Blog) and it had to be taken down for a few hours.
The upgrade instructions are here: http://codex.wordpress.org/Upgrading_WordPress
Many people do not like the new admin theme. If you don't like it have a look at this theme.
Best of luck!