The feelings of total dismay when the first rust spot is discovered on a favourite weapon are never forgotten. All tests in stage one are devised to allocate a rust prevention factor to the product under review. Weapons Grade carbon steel discs are cut, polished and blued. These discs are then coated with lubricant and subjected to various corrosive and oxidizing agents. The time the lubricant takes to break down under attack and rust to appear decides the Factor number to apply.
Higher numbers indicate the best results.
Control media used in rust tests is a proprietary industrial slush and is rated for test purposes at 30. Our expectation of the sort of rating for gun oil applied to test discs at 4. An average rating of 8-9 across the tests would be considered to be outstanding.