I just have my pet ferret run through the shotgun barrel a few times. Seriously, there have been so many posting about NOT using WD-40 on firearms. WD stands for "water displacement", and I forget what that has to do with cartridges (WD penetrates into the powder inside a cartridge?) but it's said to be bad. A pump action is a relatively simple mechanism. Presumably most lubricants will work . I just use Singer sewing machine ("All Purpose") oil on my Mossberg Maverick. Inexpensive shotgun, inexpensive oil. I have pretty much decided to sell my Smith&Wesson 686Plus .357/.38 7-shot revolver. My eyes are getting worse so I better stick to shotguns. Will be posting it for sale - for a friendly price - one of these days, probably when my present PTT expires. Sorry, Hermo. I enjoyed it until the old eyeballs got retinopathied. ***Whoops, sorry - this post was supposed to go into the "Dunkin' Donuts" thread after HEAVY's post. Clicked on wrong button, Basd eyes.