Hi, I use Forrest Bore CleaningFoam in my .223. I put my rifle into a bench rest so it's almosthorizontal with a slight tilt forward so the muzzle is lower than the butt. I take the bolt and magazine out. The Forrest can has a little pipe which I can put into the chamber and squirt the foam down the bore until it exits the muzzle. I neither block the muzzle or chamber end of the barrel, as any potential run off will exit via the muzzle into a drip tray I have. Just wipe away any foam that may be inside theaction as you withdraw the can pipe. Then let it work it's magic and patch it out when you're done.