I did that for years, but found that if that gun doesn't get shot for say, a year, rust will form under the protective film. If you shoot a lot,and clean a lot that's ok,and a lot of guys still swear by it.If on the other hand you have a sizable collection,and each piece might only get shot one or two sessions a year,or if you are in the sevice,or store your guns at a Club,it's a better idea to clean everything out with water as hot as you can reasonably stand it [think very hot bath water,not boiling] and then clean, oil, and put away as you would any modern firearm ,after taking special care to remove any trace of water.