Birchwood Casey SUPER BLUE Gun Bluing Liquid. A double-strength blueing solution designed for blueing highly polished steel parts and hardened steels containing nickel and chrome alloys. SUPER BLUE Extra Strength Gun Blue is the blackest blue. Use caution to confine the solution to the area to be reblued, as it will have an effect on the existing blue. The item "Birchwood Casey SUPER BLUE Gun Bluing Liquid Blue" is in sale since Thursday, February 19, 2009. This item is in the category "Sporting Goods\Hunting\Accessories". The seller is "thehammerfalls" and is located in Omagh. This item can be shipped worldwide.