Ok, I am new to M/Ling and I use the borebutter, but I use the presaturated patches and I am not sure how you could get a build up with using them unless a build up is reffered to as something like a thousandths of an inch. All I can say about it is that it deffinately made my guns load easier after I started using it. My guns haven't sat around long enough to get rust yet because I shoot them every chance I get.