Not cleaning a barrel is courting disaster

The controversy over whether to clean the barrel of your gun can be easily laid to rest.

The unequivocal answer is “yes.”

The consequences of not cleaning a barrel range from diminished accuracy, erratic velocity and pressure to firearm damage or personal injury.

“Barrel maintenance and cleaning are a lot like cleaning your toilet,” said Jayden Quinlan, Hornady senior ballistician. “Nobody wants to do it until either it’s overflowing or company’s coming over.”

The ballistics equivalent of an overflowing toilet can be anything from dispersion problems to shortened barrel life.

“Even people that say, ‘Never clean your barrel,’ usually add, ‘until you see pressure problems, accuracy degradation or when velocity gets more erratic,’” said Seth Swerczek, marketing communications manager.

Two good reasons to clean

The subject of whether, how and when to perform barrel maintenance is shrouded in dogma, myth and antiquated ideas. The culprits that make cleaning necessary are a bit more obvious:

1. Carbon

2. Copper

The internal ballistics cycle results in 10,000 to 65,000 psi of pressure and temperatures up to thousands of degrees Fahrenheit inside a gun’s barrel. Those two things in combination, as you burn propellant, are going to create carbon buildup.

As a bullet engraves itself into the barrel’s rifling, the lands cut themselves into the bullet’s jacket. That material has to go somewhere. Essentially, as the bullet’s traveling forward, carbon and copper are coming off the back.

Copper from the jacket and carbon can fill small cracks and pits in the bore, but after those voids are gone, it starts to build up.

As you build up carbon and copper, you’re definitely going to change the internal surface finish and the internal volume of the barrel, especially at the critical first couple of inches.

A buildup of carbon as thin as a sixth of a human hair in the first couple of inches of rifling can be worth thousands of pounds of pressure.

The amount of fouling can depend on not only pressure and temperature but also chamber dimensions, the amount of powder, the burn speed and the cartridge. A more traditional “grocery getter” — for instance, a 243 Winchester — can withstand less cleaning than a high-performance cartridge like the 6 mm Creedmoor.

Leaking primers to barrel ruptures

An entire spectrum of problems can follow improper barrel maintenance. On the low end are performance problems such as leaking primers, issues with extraction and locking up the firing pin. On the high end are things like barrel ruptures and bolt lug shears.

“Some crazy high-pressure events could occur if this goes unaddressed,” Quinlan said.

While the average shooter isn’t in a high-risk environment, the stakes are much higher for those in law enforcement and the military who count on their firearms to function properly.

Performance problems such as erratic pressure and degrading accuracy may be signs that a barrel is due for a good cleaning, although there’s no one-size-fits-all answer to the question of when.

Solvent is the solution

With 500 barrels in service in its ballistics lab, Hornady has learned a thing or two about how to clean a barrel effectively.

The key to any good barrel-cleaning regimen begins with the solvent. Find a good, effective solvent, and let the solvent do the work. The solvent is what’s going to actually break up the carbon or the copper buildup and allow you to remove it.

The Hornady ballistics lab uses solvents like Bore Tech Eliminator, among several others that are mild and nonhazardous with no volatile organic compounds, but shooters should find a product that works for them.

“You’ll want to wet the bore and remove any larger, loose deposits by pushing several solvent soaked patches down. Then it is ready to brush,” said Matt George, lead ballistics lab technician at Hornady.

About 20 strokes with a nylon brush can help aerate the solvent and make it more effective. Then let it soak for about 30 minutes, patch it out dry and clear out any residue with isopropyl alcohol. Then check it with a bore scope.

More stubborn buildup may call for something abrasive, such as Bore Tech’s bore polishing cleaner, Chameleon. A paste like J-B bore-cleaning compound or Iosso are the top end of what most shooters should use.

The more abrasive the cleaner, the more important it is to go slowly because of the potential to damage the barrel.

After cleaning and checking with a bore scope, try shooting some reference ammunition — cartridges of a known quality — to see if the firearm’s performance has improved.

To learn more

For more information on cleaning your barrel, watch or listen to the following podcast episodes for an in-depth discussion on why barrel cleaning and maintenance is necessary.

Ep. 103 Should you clean your barrel? Part I

There’s a lot of myth and dogma surrounding barrel cleaning. What kind of barrel maintenance schedule should you keep, how should you clean a barrel, and should you even clean it at all? This episode lays the groundwork for why barrel cleaning and maintenance is necessary and what can happen if a barrel goes neglected.

Ep. 114 Barrel Cleaning Part 2

The guys dive deep into best practices for barrel cleaning, carbon rings, products used, and much more.