I have been using Montana Bore Conditioner in several stainless and Blue Bores. Never had an issue with them stored for long periods (1 to 2 years). I have one ML (Knight KRB7) that had an issue when shooting BH209 where it sort of formed a Crud Ring. I reported it hear way back when I was working on a Mod for this rifle, maybe 6 or 7 years ago. I know this is pretty much never heard of but this rifle does it and it is the only one of 4 that I have and do shoot BH in. There must be some anomaly in the bore that you just can't see. Bore cleans up smooth and shinny. That Bore has had Numerous Rounds with JB too and it still did it. Switched to Montana Bore conditioner and after just a few treatments the Crud does not build up no where near what it did and what there is, is soft and I can reload without swabbing unlike before. Have no Idea why or how it worked but it worked wonders for this rifle. A Bit over a year and a half ago I stripped the bore and gave it a BoreTek Treatment that has helped it too. For some of the guns I have worked on and restored for family that don not get shot much I put Breakfree Collector in it.