I found this forum while searching for a local supplier of 100% silicone oil. I need it for a totally different application than you do. I have to say that there is a lot of misinformation going around here. The Permatex Dielectric Tune-Up Grease that you are talking about is NOT 100% silicone oil (or "silicone" as you put it) at all. According to the MSDS at the Permatex site, it is ">70% POLYDIMETHYLSILOXANE" (that's your 'silicone oil'), "<10% MODIFIED SILICON DIOXIDE" (some "sandy" filler), "0.5-5.0% OXIRANE, METHYL-, POLYMER (whatever that is). So it is around 70% silicone oil with the rest being fillers. I don't know how pure you need it for your application but I'd like it as close to 100% as possible for mine. That silicon dioxide bothers me. It is silica, sand. Granted it's milled to a fine dust but do you want that in your gun? I read in another forum that it can abrade o-rings. Don't forget, this is made to prevent high voltage arcing in distributor caps, not for lubrication. RC silicone "shock oil", which is like $5 for 2 fl. oz. on eBay, seems to be 100% silicone oil by the description but I won't be convinced until I see the MSDS. I have not been able to find one for any brand so far. It may "contain 100% silicone oil" but what percent of the product is the pure oil? Like you pointed out about CRC's 808 "Pure Silicone Spray Lube"--10-30%. And CRC's FOOD GRADE SILICONE is even worse. It has only "2-5% DIMETHYLPOLYSILOXANE". The rest is HEXANE ISOMERS (55-65%) and 1,1-DIFLUOROETHANE (30-40%). This is "food grade"?! I saw this recommended in another thread on this forum. Can anybody give me a link to an MSDS for any of the RC shock oils? That seems to be the best bet.