Standard Cleaning - Rifle

Begin by preparing your rifle for cleaning. This should include protecting your scope with some form of lens cover. Brushes soaked with solvent can create a fine spray or mist of solvent upon exiting the muzzle, some of which will invariably be blown back onto the scope. Modern bore-cleaning solvents are quite strong and can severely damage the lens coatings of a fine scope. This can easily be avoided simply by covering the lenses before you break out the solvent, brushes or other cleaning materials. A second item we strongly recommend is a stock boot. A stock boot is a protective cover that is draped over or wrapped around the butt of a rifle to protect it from solvents during cleaning. While it will protect the finish of the rifle, its real benefit is to keep the solvent from dripping into the area around the tang. Solvents or oils seeping into this area will attack the bedding, rendering it soft or “punky” and destroying accuracy. There are commercial stock boots available through several of the better competitive suppliers, such as Sinclair International. A heavy towel backed by plastic can serve the same purpose, preventing solvent from reaching the stock. With the rifle set into a cradle or vise, we’re ready to begin cleaning.

Start by placing the bore guide or muzzle protector in place and wiping the rod thoroughly with a clean, solvent-dampened rag. Make this a habit every time you run a rod through the bore! Standard cleaning techniques usually call for swabbing the bore with a patch soaked with one of the milder solvents, such as Hoppe’s #9 or Shooters Choice MC-7. This is best done with a loop-type patch holder, rather than a jag; the patch will hold more solvent and allow better saturation of the bore. The solvent should loosen any powder or metal fouling that may be in the bore, enough that a second patch on a tight-fitting jag will allow its easy removal. If a jag is used to initially apply the solvent, make sure that it is not too tight a fit. Remember, the solvent provides the cleaning action chemically and does not require scrubbing. A jag that is too tight will merely serve to wring out the patch, actually decreasing the amount of solvent you are applying to the fouling. Leave the solvent to soak in the bore for a few minutes, then swab the barrel out with a dry patch. Repeat this process a second time, noting the condition of the last patch. If there are traces or streaks of blue or green (depending on the type of solvent and its ammonia content) present, this shows copper fouling. You may wish to repeat this process until the fouling has disappeared. At this point, we are ready to move on to brushes. Thread a bronze brush onto the rod and apply a few drops of solvent. In doing this, never dip the brush directly into the bottle; you will contaminate the remainder of the solvent and weaken it. We have found that the small plastic bottles available at drug stores are ideal for this.

Equipped with a closeable spout, they will allow solvent to be dribbled directly onto the brush, avoiding the temptation to dip the brush directly into the solvent. Guide the rod into the bore and run it back and forth all the way through the bore for several strokes. When doing so, NEVER try to reverse directions while the brush is in the barrel; run it completely out the bore, and then reverse the direction. Repeat this procedure 10 to 12 times, or until the fouling is removed. Once you have finished with the brush, flush it thoroughly with Gun Scrubber, MEK, or a similar cleaner/degreaser. Fitting a jag tip to the rod, run a wet patch or two through the bore, followed by several dry patches. Inspect the bore for any signs of fouling still in the barrel and watch the patch for a blue or green discoloration caused by metal fouling. If there are none, the barrel is clean. If this discoloration and/or copper fouling is still present, we have more work to do.

One method of using the milder solvents on badly fouled bores is to use a chamber plug and soak the bore. In practice, a cartridge shaped chamber plug fitted with a rubber or silicone “O” ring is chambered in the rifle. With the “O” ring sealing the chamber, the bore is filled with solvent and left standing upright (muzzle up) for eight to 10 hours, or more if the fouling is severe. After this has been done, follow it up with a normal cleaning as outlined in the previous paragraph. Before using this method, make sure you check with the manufacturers instructions, as some solvents need oxygen to work and are obviously not suited to this procedure.

Another option for stubborn copper fouling is to resort to one of the stronger solvents, such as Sweet’s 7.62, CR-10 or Shooter’s Choice Copper Remover, which are specially formulated to dissolve copper. These solvents are used with a jag tip and patches only, not a brush. Saturate a patch with the solvent and run it through the bore, discarding it after one pass. Allow the solvent to soak in the bore for 10 to 15 minutes, and run a second solvent-soaked patch through the bore. If the patch comes out blue, you still have traces of copper fouling present. When the second patch comes out with no blue streaking, the bore is clean. Bear in mind that these solvents are extremely strong and cannot be left in the bore for more than about 20 minutes. We have seen bores etched when ammonia-based solvents were left in too long, so use them with appropriate discretion and follow the manufacturer’s instructions to the letter. Rubber gloves are strongly recommended with these solvents, as they can irritate the skin during prolonged contact. When using any solvent, proper ventilation is essential.

If you want to avoid the harsh ammonia solvents, you may wish to consider a mild abrasive cleaner, such as JB Bore Compound or Rem-Clean. We have had excellent results with both cleaners here in the Sierra ballistic lab. In use, the cleaning compound is applied to a tightly fitted patch (most manufacturers recommend a patch wrapped around a worn-out bore brush), and run through the bore eight to 10 strokes. In doing this, make sure the patch does not fully exit the bore, or it will be wadded up or stripped off when the brush reenters the muzzle. Rods equipped with a stop collar, or even marked with a simple wrap of masking tape, will provide a reference point to stop before running the rod entirely out the bore. If the process needs to be repeated, a fresh application of the compound should be made, as it breaks down very quickly, rendering it ineffective. As when using the various copper solvents, read the manufacturer’s directions and follow them to the letter.

After an abrasive compound has been used, the bore should be given a quick but thorough brushing or swabbing with a good solvent. After the bore has been completely cleaned, a light coating of oil may be in order if the gun is to be stored. Bear in mind that if too much oil is used, it may seep back into the action and down into the bedding. If a rifle’s bedding becomes oil or solvent damaged, serious loss of accuracy will result. Ideally, rifles should be stored muzzle down to prevent oil or other cleaning fluids from running back down the bore, into the action, trigger and bedding.

28% Stronger Ammonia Treatment

A 28% Stronger Ammonia treatment was the solution to metal fouling used by military ordnance departments in years gone by. With the development of more effective commercial bore-cleaning solvents, this treatment has pretty well faded away, although a shooter may still hear it mentioned. A complete discussion of this method (with the formula and mixing instructions for the solution) can be found in Col. Whelen’s Small Arms Design, Vol. II, as well as Maj. Gen. Julian Hatcher’s classic, Hatcher’s Notebook. While it was extremely effective, the solution had its drawbacks.

In use, the 28% Stronger Ammonia solution had to be mixed up fresh for each cleaning, since its shelf life was extremely limited. Once mixed, the solution needed to be used immediately, as it could not be exposed to air for more than about five minutes. This meant the rifle(s) to be done had to be prepared for cleaning prior to mixing the solution. This was accomplished by tightly plugging the chamber and fitting a small section of rubber hose over the muzzle. As soon as the solution was mixed, it was poured into the barrel. With the bore completely filled, the rifle was allowed to stand for not more than 30 minutes before the solution had to be removed. After the treatment, the rifle would be cleaned with water, dried, cleaned again with standard cleaning solvents and oiled thoroughly.

Although it was effective, the 28% Stronger Ammonia treatment was very harsh. If the solution was allowed to evaporate on exposed metal, it caused rusting almost immediately. If used on a barrel that was too warm, the solution attacked the steel and instantly ruined the bore. When the solution was spilled on the stock, it would discolor or “burn” the wood. Even when mixed and used properly, Maj. Gen. Hatcher mentions that on occasion the solution would attack the steel for no apparent reason, ruining the barrel. An effective way to remove fouling, yes, but perhaps a bit too much of a good thing. The 28% Stronger Ammonia solution is presented here more as a point of historical interest, since it is occasionally mentioned today.