Small Arms Firing Manual
Cleaning the Rifle
a. The proper care of the bore requires conscientious, careful work, but it pays will in the attainment of reduced labor of cleaning, prolonged accuracy life of the barrel, and better results in target practice. Briefly stated, the care of the bore consists in removing the fouling resulting from firing, to obtain a chemically clean surface with a film of oil to prevent rusting. The fouling which results from firing is of two kinds–one, the products of combustion of the powder; the other cupro-nickel scraped off (under the abrading action of irregularities or grit in the bore). Powder fouling because of its acid reaction, is highly corrosive; that is, it will induce rust and must be removed. Metal fouling of itself is inactive, but may cover powder fouling and prevent the action of cleaning agents until removed, and when accumulated in noticeable quantities it reduces the accuracy of the rifle.
b. Powder fouling may be readily removed by scrubbing with hot soda solution, but this solution has no effect on the metal fouling of cupro-nickel. It is necessary, therefore to remove all metal fouling before assurance can be had that all powder fouling has been removed and that the bore may be safely oiled. Normally, after firing a barrel in good condition the metal fouling is so slight as to be hardly perceptible. It is merely a smear if infintestimal thickness, easily removed by solvent of cupro-nickel. However, due to pitting, the presence of dust, other abrasives, or to accumulation, metal fouling may occur in clearly visible flakes or patches of much greater thickness much more difficult to remove.
c. In cleaning the bore after firing it is will to proceed as follows: Swab out the bore with soda solution (subparagraph j) to remove powder fouling. A convenient method is to insert the muzzle of the rifle into the can containing the soda solution and with the cleaning rod inserted from the breech, pump the barrel full a few times. Remove and dry with a couple of patches. Examine the bore to see that there are in evidence no patches of metal fouling which, if present, can be readily detected by the naked eye, then swab out with the swabbing solution- a dilute metal fouling solution (subparagraph j). The amount of swabbing required with the swabbing solution can be determined only by experience assisted by the color of the patches. Swabbing should be continued, however, as long as the wiping patch is discolored by a bluish-green stain. Normally a couple of minutes work is sufficient. Dry thoroughly and oil.
d. The proper method of oiling a barrel is as follows: Wipe the cleaning rod dry; select a clean patch and thoroughly saturate it with sperm oil or warmed cosmic, being sure that the cosmic has penetrated the patch; scrub the bore with the patch, finally drawing the patch smoothly from the muzzle to the breech, allowing the cleaning rod to turn with the rifling. The bore will be found now to be smooth and bright so that any subsequent rust and sweating can be easily detected by inspection.
e. If patches of metal fouling are seen upon visual inspection of the bore the standard metal fouling solution prepared as hereinafter prescribed must be used. After scrubbing out with the soda solution, plug the bore from the breech with a cork at the front of the chamber or where the rifling begins. Slip a 2-inch section of rubber hose over the muzzle down to the sight and fill with the standard solution to at least one half inch above the muzzle of the barrel. Let it stand for 30 minutes, pour out the standard solution, remove hose and breech plug, and swab out thoroughly with soda solution to neutralize and remove all trace of ammonia and powder fouling. Wipe the barrel clean, dry, and oil. With few exceptions, one application is sufficient, but if all fouling is not removed, as determined by careful visual inspection of the bore and of the wiping patches, repeat as described above.
f. After properly cleaning with either the swabbing solution, or the standard solution, as has just been described, the bore should be clean and safe to oil and put away, but as a measure of safety a patch should always be run through the bore on the next day and the bore and wiping patch examined to insure that cleaning has been properly accomplished. The bore should then be oiled, as described above.
g. If the swabbing solution or the standard metal fouling solution is not available, the barrel should be scrubbed, as already described, with the soda solution, dried and oiled with a light oil. At the end of 24 hours it should again be cleaned, when it will usually be found to have “sweated”; that is, rust having formed under the smear of metal fouling where the powder fouling was present, the surface is puffed up. Usually a second cleaning is sufficient, but to insure safety it should be again examined at the end of a few days, before final oiling. The swabbing solution should always be used, if available for it must be remembered that each puff when the bore “sweats” is an incipient rust pit.
h. A clean dry surface having been obtained, to prevent rust, it is necessary to coat every portion of this surface with a film of neutral oil. If the protection required is but temporary and the arm is to be cleaned or fired in a few days, sperm oil may be used. This is easily applied and easily removed, but has not sufficient body to hold its surface for more than a few days. If rifles are to be prepared for storage or shipment, a heavier oil, such as cosmic, must be used.
i. In preparing arms for storage or shipment they should be cleaned with particular care, using the metal fouling solution as described above. Care should be taken, insured by careful inspection on succeeding day or days that the cleaning is properly done and all traces of annonia solution removed. The bore is then ready to be coated with cosmic. At ordinary temperatures cosmic is not fluid. In order therefore, to insure that every part of the surface is coated with film of oil the cosmic should be warmed. Apply the cosmic first with a brush; then with the breech plugged, fill the barrel to the muzzle, pour out the surplus, remove the breech-block, and allow to drain. It is believed that more rifles are ruined by improper preperation for storage than any other cause. If the bore is not clean when oiled–that is powder fouling is present or rust has started–a half inch of cosmic on the outside will not stop its action, and the barrel will be ruined. Remember that the surface must be cleaned before the heavy oil is applied. If the instructions as given above are carefully followed arms may be stored for years without harm.
j. Preperation of solutions:
SODA SOLUTION.–This should be a saturated solution of sal soda (bicarbonate of soda). A strength of at least 20 per cent is necessary. The spoon referred to in the following directions is the model 1910 spoon issued in the mess outfit. Sal soda, one fourth pound, or four (4) heaping spoonfuls. Water, 1 pint of cup model of 1910, to upper rivets. The sal soda will dissolve more readily in hot water.
SWABBING SOLUTION.–Ammonium persulphate, 60 grains, one half spoonful smoothed off. Ammonia, 28 percent, 6 ounces, or three eights of a pint, or 12 spoonfuls. Water, 4 ounces, or one fourth pint, or 8 spoonfuls. Dissolve the ammonium persulphate in the water and add the ammonia. Keep in tightly corked bottle; pour out only what is necessary at the time, and keep the bottle corked.
STANDARD METAL FOULING SOLUTION.–Ammonium carbonate, 200 grains, or 1 heaping spoonful. Ammonia, 28 per cent, 6 ounces, or three eights pint, or 12 spoonfuls. Water, 4 ounces, or one fourth pint, or 8 spoonfuls.
Powder the persulphate and carbonate together, dissolve in the water and add the ammonia; mix thoroughly and allow to stand for one hour before using. It should be kept in a strong bottle, tightly corked. The solution should not be mixed with unused solution, but should be bottled separately. The solution, when mixed should be used within 30 days. Care should be exercised in mixing and using this solution to prevent injury to the rifle. An experienced noncommissioned officer should mix the solution and superintend its use. Neither of these ammonia solutions have any appreciable action on steel when not exposed to the air, but if allowed to evaporate on steel they attack if rapidly. Care should, therefore, be taken that none spills on the mechanism and that the barrel is washed out promptly with soda solution. The first application of soda solution removes the greater portion of powder fouling and permits a more effective and economical use of ammonia solution. These ammonia solutions are expensive and should be used economically.
k. It is a fact recognized by all that a highly polished steel surface rusts much less easily than one which is roughened; also, that a barrel which is pitted fouls much more rapidly than one which is smooth. Every effort, therefor, should be made to prevent the formation of pits, which are merely enlarged rust spots, and which not only affect the accuracy of the arm but increase the labor of cleaning.
l. The chambers of rifles are frequently neglected because they are not readily inspected. Care should be taken to see that they are cleaned as thoroughly as the bore. A roughened chamber delays greatly the rapidity of fire, and not infrequently causes shells to stick.
m. A cleaning rack should be provided for every barrack. Rifles should always be cleaned from the breech, thus avoiding possible injury to the rifling at the muzzle, which would affect the shooting adversely. If the bore for a length of 6 inches at the muzzle is perfect, a minor injury near the chamber will have little effect on the accuracy of the rifle. The rifle should be cleaned as soon as the firing for the day is completed. The rifle should be cleaned as soon as the firing for the day is completed. The fouling is easier to remove then, and if left longer it will corrode the barrel.
n. The principles as outlined above apply equally will for the care of the barrel of the automatic pistol. Special attention should be paid to cleaning the chamber of the pistol, using the soda solution. It has been found that the chamber pits readily if it is not carefully cleaned, with the result that the operation of the pistol is made much less certain.