Firearm Freedom Woes

[sinsix]

I didn't think this was possible, but I got the Melee Mayhew Achievement without gaining the firearm freedom award. Does anyone know the shortest way to get each gun type? I've been back through this twice and still have not used each weapon apparently. Am i correct in assuming the weapons are one .45 Cal Pistol, Revolver, Sawed-off Shotty, Pump Shotty, SMG, and Rifle?

[Norad45]

http://www.xbox360achievements.org/forum/showthread.php?t=1035


^ Shows you what weapons are in each chapter.

[Norad45]

Also, (I forgot to say) I think you need to finish each level after you shoot somebody with a weapon in order for it to go to the Firearm Freedom