A few weeks ago I undertook the task of cleaning a 6mm BR that had not been treated with Modern Spartan System products. It had had about 100 rounds shot through it since cleaning. What a chore! It took several cycles with wet and dry patches with standard carbon cleaner, then the same with a popular copper cleaner. I quit counting patches at 100! My dad then gave me all of the MSS products. I then completely treated it with Spartan Accuracy Oil and Accuracy Grease, went to the range and went through the complete optimization break-in procedure that you can see on their “It’s All About the Accuracy” video. I took it prairie dog shooting and shot over 300 rounds without cleaning, or even using a bore snake. This morning I decided to thoroughly clean the BR, but was dreading the time and effort it would take. What a surprise! Wet patched it with Carbon Destroyer with two patches and then 4 dry patches…CLEAN!! I used the Copper/Lead Destroyer cleaner but no blue markers. There was no copper fouling! I don’t know how it does it but this stuff not only makes a gun shoot better, but using it all the time makes cleanup a breeze! I’ll never use anything else.