I've got a Champion Victory-35 and its rated for 60 minutes at 1300 degrees with an internal temperature of 322 degrees.
Most safes are rated for how long they will keep the internal temperature below the burning point of paper.
I found this description at
http://www.southlandsafes.com/chmpn_fire_protection.htm
Papers and documents char at temperatures around 405°. Guns are damaged from temperatures exceeding 500°. To protect documents and other possessions during a home fire, the internal temperature of the safe should remain below 350°. This is why we include Phoenix Fire Protection standard on all models--so your safe's contents won't end up cremated.
Five Levels of Fire Protection
Phoenix Class I Fire Protection
30 Minutes at 1200°F. -- Standard on Sport
Phoenix Class II Fire Protection
45 Minutes at 1250°F.
Phoenix Class III Fire Protection
1 Hour at 1350°F. -- Standard on? Trophy
Phoenix Class IV Fire Protection
1 Hour 30 Minutes at 1500°F. -- Standard on Triumph
Phoenix Class V Fire Protection
2 Hours at 1500°F. -- Standard on Crown
Hope this helps