ORIGINAL: Jackson Bowner

My father used to say about car engine maintenance that you can never do too many oil changes. The analogy here is that a clean barrel will out live and out performa dirty barrelover time.Copper fouling from the bullet does more to affect accuracy than most people realize. Sub MOA rifle barrels would loose their accuracy if the copper and foulingwas not removed frequently after just a few shots (around 10 shots), and so these barrels are frequently cleaned with solvents down to a bare metal. It takes several shots to first heat then "foul" a cold clean barrel so velocities stabilize and optimum accuracy can be achieved. This is because initial shots through a clean barrel produces different frictional energy until lube is blown out and the bore is coated with powder residue and/or copper so bullet friction begins to stabilize. Soft metals gall and stick to similar metal. Each round fired through the barrel will deposit a little more copper until eventually accuracy deteriorates. Once a barrel is fouled successive shots will not remove the copper.Copper fouling is usually deposited in patches and lumps resulting in a rough bore which promotes the tearing of the tail portion of the bullet jacket as it passes through the bore. This adds air turbulence at the base of the bullet so it does not fly as true. All barrels foul. It is simply a matter of how many shots are needed to first stabilize velocity then how quickly it fouls so severely the gun starts "tossing flyers". Obviously, if it takes nearly 10 shots for velocities to stabilize and at that point the barrel is fouled so severely accuracy is impossible, you have a problem. The barrel is called a "fouler". So, "to clean or not to clean, that is the question". I'll leave the answer to you, but for me, the ole adage and analogy that my father gave me about oil changes when I was a kid still rings true today!