I started to post this info as a reply to another thread, but then decided that perhaps it deserves its own thread: Nearly all military ammo is waterproofed- the primer gets a tiny dab (well, sometimes a big glob) of red lacquer, and the case mouth gets either a black tarry paint inside or more lacquer on the outside. Other folks who have tested things say that the inside-mouth sealer (black stuff) is distinctly better than lacquer on the outside of the bullet-case joint. Twenty years ago, most civilian ammo got the same treatment. I can remember even Winchester white box USA 9mm fmj having sealed bullets and primers. Federal used a clear lacquer on the primers instead of red, but the stuff was there to do the job. About ten years ago I noticed that the Winchester 115 gr +P+ that our department issues, no longer had the black mouth sealer. Phoned Winchester and they said the EPA was after them because of fumes from the solvent used in the black sealer. They could still use it for federal government ammo but most civiliam ammo was not going to get it. More recently, the primer sealant has also disappeared from Winchester, even on our duty ammo. Recent production Speer Gold Dot ammo also appears totally unsealed. I don't have any Federal pistol ammo on hand, but some of their recent production .375 H&H rifle stuff has red sealed primers and perhaps black stuff inside the case mouths- good. But Africa-bound ammo sometimes gets extra attention. Does it all make any difference? Only if your ammo gets exposed to water or oil. Keep in mind that if your gun gets dunked and you are unable to clean it up right away, there may be a few drops of water trapped in just the wrong places against your cartridges. Break Free CLP seems to slowly disolve the red primer sealant so don't count on the paint to protect you from all that oil you slobbed into your firing pin channel ;P When I tested it after 24 hrs under 1" of water, 9mm ammo that was totally unsealed had an occasional misfire. After a week under water the missfire rate went up over 50%. After being heavily sprayed with Break Free CLP, even the unsealed ammo fired normally at the end of the week. But Break Free is said to be much easier on primers than some other types of oil, so we can't count on others. WD-40 is said to be especially bad. As the old saying goes, "Keep your powder dry"