ing of the receiver, at an angle of 45 degrees, so it will reflect light into the bore. Hold the ejection opening towards the light, and examine the bore from the muzzle, eye about 8 inches from the muzzle. If small smears, flakes, or lumps are seen on the surface of the bore near the muzzle, or for about 6 inches down from the muzzle, looking like dull lead, this is metal fouling. Metal fouling should be removed at once, as it not only is detrimental to the best accuracy, but the bore will rust very quickly on the portions covered by this fouling. To remove metal fouling, proceed as follows: The rifle should be clean, the barrel cold, and the bore free from primer and powder fouling and oil. Place a cork in the chamber so as to seal the bore at that point, plug the gas port tightly with a small wooden plug, and stand the rifle muzzle up. Carefully pour the standard metal fouling solution into the bore from the muzzle until the solution rises in the flash hider above the bore. Take care not to spill any solution on the exterior of the rifle or on the stock. If any is spilled wipe it off at once. Place a few drops of oil on top of the solution to prevent the ammonia from evaporating and rusting the flash hider. The solution should be permitted to remain in the bore from 15 to 20 minutes, never longer than 30 minutes under any circumstances. The solution should never be used in a hot barrel. Then pour the solution out of the bore, remove the cork from the chamber while holding the muzzle depressed to prevent leakage of ammonia into the receiver, remove plug from gas port, swab out the ammonia remaining, swab with water to remove all traces of ammonia from the bore, then dry the bore thoroughly, and oil as prescribed for regular cleaning. The flash hider should be removed and threads on barrel and flash hider cleaned of all traces of ammonia solution. The ammonia solution dissolves the metal fouling. Where tracer ammunition has been used, it may be necessary to apply the solution three or four times to remove the large amount of metal fouling deposited. The standard metal fouling solution is prepared as follows: Ammonia persulphate-One ounce, or two medium heaping spoonfuls. The spoon referred to is the model of 1910 spoon issued in the mess kit. Powder the persulphate and carbonate together by placing inside a clean cloth and grinding with tool handle; dissolve in the water and ammonia; mix thoroughly until about 90 per cent of the powder is dissolved, then use at once or bottle for future use. It should be kept in a strong bottle, tightly corked with rubber cork, and in a cool place. In order to preserve the strength of the solution the bottle should be opened only for the time necessary to pour out the amount required. The solution, when mixed, should be used within 30 days. The above amount is sufficient to clean about 6 barrels. The solution should not be used more than twice, and used solution should not be mixed with unused solution, but should be bottled separately. Care should be used in mixing and using this solution to prevent injury to the rifle. It should never be used in a warm barrel. Fresh solution has no effect on steel if the steel be kept continually wet or immersed for not more than 30 minutes. If the solution be allowed to evaporate on steel the latter will rust very quickly. When new type ammunition, containing bullets jacketed with copper (gilding metal), is used the ammonia swabbing solution will usually suffice to remove the slight, thin plating of copper on the surface of the bore which sometimes occurs with such ammunition. After the bore has been cleaned with one of the water solutions as recommended in subparagraph b (2), wet a number of cut flannel patches with the ammonia swabbing solution and swab the bore with these, generally for about 5 minutes, or until the patches no longer show a blue color. Then swab again with water, and dry and oil the bore. Ammonia swabbing solution may be made by mixing one and one-half parts of 28 per cent ammonia to one part of water. Or a stronger solution may be made by taking ammonium persulphate, 60 grains or 1⁄2 spoonful smoothed off, ammonia 28 per cent, 6 ounces or 12 spoonfuls, and water, 4 ounces or 8 spoonfuls. Dissolve the ammonium persulphate in the water and add the ammonia. Keep in a tightly corked bottle, pour out only what is necessary at the time, and keep the bottle corked. The ammonia swabbing solution will have little effect on the heavy, lumpy metal fouling which sometimes occurs when the older bullets jacketed with cupronickel are used, and is intended for use when the newer ammunition, loaded with bullets jacketed with copper (gilding metal), is used. c. Cleaning the Chamber-During the firing a certain amount of oil and dirt accumulates in the chamber, where the heat forms it into a hard coating, akin to carbon, on the walls of the chamber. This coating is easily removed with the automatic rifle cleaning brush while the chamber is hot, but is difficult to remove after it hardens upon cooling. If not removed, cartridges stick in the chamber, resulting in failure to extract. The automatic rifleman should be trained to use the cleaning brush immediately upon cessation of firing, even if this cessation is only for a few minutes. The cleaning brush is introduced through the ejection opening in the receiver, and should be used vigorously. Upon final completion of firing, the brush having been used, the chamber is further cleaned in the process of cleaning the bore, care being taken that water does not remain in the chamber, and that finally the chamber be wiped dry with a patch wrapped around the forward portion of the cleaning brush, and finally lightly oiled in the same manner. d. Cleaning the gas system.-The gas system consists of the gas cylinder, gas cylinder tube, piston, and the included gas ports. All of these are subjected to primer and powder fouling to the same extent as the bore, and also receive carbon deposits from the burning of oil. To clean these parts of powder and primer fouling, wipe and scour them thoroughly with rags or patches wet with soap and hot water, or with hot water only, with the aid of the gas cylinder tool. Then using dry rags or patches thoroughly dry the parts. Scrape off any carbon deposits remaining with the gas tool, and wipe clean and dry again. Then oil the parts with a thin film of lubricating oil, (Q. M. specification No. 2-27), applied with a clean rag or patch. Do not use an oil can or lubricate excessively. This is sufficient lubrication for these parts. Excessive oil produces excessive carbon and dirt that causes friction. c. Cleaning of remainder of rifle.—(1) Breech mechanism.—This refers to the receiver and all parts contained therein. These parts should be wiped with oily rags, and then with a clean dry rag so as to render thoroughly clean and dry. They should then be wiped with a clean rag slightly saturated with lubricating (sperm) oil, (Q. M. specification No. 2-27), so as to give to each Exces part a thin film of light oil. This is sufficient for perfect lubrication. sive oiling, as with an oil can, is a waste of oil, and results in a collection of dirt, which causes friction. (2) Magazines.--Magazines should be stripped, wiped clean and dry, and thinly coated with oil as described for the breech mechanism. Much dirt gets into them through careless handling on the ground during range or other firing. They must be kept free from dirt and rust which hinder their operation by making the spring and follower stick. Care must be exercised in the handling of magazines to avoid denting or bending them. (3) Exterior and stock.-Clean, dry and lightly oil all metal parts. Wipe all dirt out of screw heads and crevices with small brush or match stick. If the rifle is to be placed in the arms rack after cleaning, the soldier should avoid touching the oiled metal parts with the hand, as perspiration is a great promoter of rust. Ordinarily the stock and forearm need only be wiped dry and then wiped with an oily rag. About once a month or oftener, and always after the stock and forearm have become wet with water or perspiration, they should be thoroughly rubbed with a little linseed oil in the palm of the hand. Rub the oil well in until dry. An old tooth brush may be used on the checked portion of the forearm. Before firing all oil should be removed from the exterior of the barrel in order to prevent smoking when the barrel becomes hot. 27. Rifles in storage.—a. Preparation for storage and shipment.--Rifles which have been withdrawn from issue to enlisted men, from whom they received proper care at short intervals, should be stored in arms chests in the organization storeroom. When thus stored, even for a short period, or when they are to be shipped, either by rail or water, they should be cleaned and prepared with particular care. The bore should invariably be cleaned with the standard metal fouling solution as described in subparagraph b (3), after which the bore should be thoroughly washed with water to insure that all traces of the solution are removed. The bore, all parts of the mechanism of the rifle, and the exterior should be thoroughly cleaned and then dried perfectly dry with rags. In damp climates particular care must be taken to see that the rags are dry. After drying a part, the bare hands should not touch that part. All metal parts should then be heavily coated with cosmic, known as rust-preventing compound, semisolid (Q. M. specification No. 2-53). The cosmic should be warmed slightly and applied with a brush. The bore should be plugged and poured full of cosmic, the surplus poured out, the plug removed, and the bore allowed to drain. Special care should be taken to insure that the gas system is thoroughly cleaned and greased, and that the gas ports are free from fouling. Then handling the rifle by the stock and forearm only, it should be placed in the arms chest, the wooden supports at the butt and muzzle having previously been painted with cosmic. Under no circumstances should a rifle be placed in store contained in a cloth or other cover, or with a plug in the bore. Such articles collect moisture which causes the weapon to rust. b. Rifles issued from storage.-Rifles when issued from storage are normally found completely covered with heavy grease (cosmic). Grease may be removed by the use of gasoline or kerosene as may be convenient, or may be wiped from the parts with a cloth. In all cases where gasoline or kerosene are used for cleaning purposes, care should be taken to see that they are completely removed from the parts by wiping, washing with soap and water, and drying. All surfaces having been wiped clean, they should then be protected and lubricated with a thin film of lubricating oil, (Q. M. specification No. 2-27), applied with a rag. See that all heavy grease is removed from the gas system and gas ports, and from the firing pin. Particular care must be taken to see that all grease is removed from the bore and chamber before firing, as grease in these parts may cause high and dangerous breech pressure, or the barrel may even burst on firing if it be filled with heavy grease. 28. Points to be observed before, during, and after firing.-a. Before firing (1) Test trigger mechanism at safe (A), and (F). (2) See that bore is clear and clean. (3) Work slide back and forth rapidly several times to see that it moves freely and does not stick. (4) Test ejector and extractor with dummy or empty case. (5) Verify proper setting of gas port. (6) Verify oiling. (7) Verify cleaning. (8) Examine magazines and eliminate faulty ones. (9) See that kit contains oil can full of oil and full complement of spare parts. b. During firing (1) Keep magazine and chamber protected from dirt. (2) Do not allow rifle to become dry. (3) Clean bore and gas system frequently. c. After firing (1) Remove loaded magazine. (2) Let bolt forward. (3) Wipe out bore and oil rifle. (4) Clean rifle thoroughly at first opportunity. (5) Replenish spare parts. (6) Reload magazines as soon as possible. 29. Protection of guns against gas.--a. When rifle can not be dismounted.— (1) Wipe over with a well-oiled rag all surfaces exposed to the gas except bore. (2) Fire occasional shots and between these work operating handle back and forth. (3) Wipe magazines and spare parts with oiled rag and replace in belts. b. When rifle can be dismounted.-Proceed as above, except that the bore should be plugged at each end with an oiled rag and the rifle stripped, wiped with oil, assembled, and if possible wrapped in a waterproof sheet. c. After the attack.-(1) Clean all parts in boiling water with a little sal soda. (2) Clean bore thoroughly. (3) Wipe all trace of gas from contents of spare-parts case. (4) If time permits, soak belt equipment for 2 hours in solution containing 1 part soda, 3 parts soft soap, and 10 parts water. Then scrub the belt and hang it up to dry. Section VII DETAILED DESCRIPTION OF GUN Detailed description of gun... Paragraph 30 30. Detailed description of gun.-The rifle can best be described under two headings: The stationary portions and the moving portions. a. The stationary portions consist of the receiver and parts directly or indirectly attached thereto. The receiver (1) is made of a single piece of steel formed at the rear end to receive the butt stock (125) and the buffer tube (65), which latter part is threaded into the receiver. The butt stock is held in place by the butt-stock bolt (126) which threads into the rear end of the buffer. The buffer tube contains, from front to rear, the buffer (66), four sets of buffer friction cups (68) and cones (67), the buffer spring (70), and the buffer nut (69). The bronze buffer friction cups fit over the steel cones and are split to allow expansion when under pressure. The butt plate (130) is attached to the butt stock by means of screws (136 and 137). Butt plate is provided with a trap (131) which when open will allow the removal of the butt-stock bolt. The butt swivel plate (150) is fastened to the bottom of the butt stock by means of screws (151). To this bracket is attached the swivel link (inner) (148) and swivel link (outer) (149), and the swivel (143) by means of swivel screws (147). This swivel arrangement provides a three-way motion for the gun-sling strap connection. The marking for the rifle is rolled on the top of the receiver at the front end. In rear of this marking the top plate (2) is fitted into dovetail guides in the receiver. The rear-sight base (94) is driven into dovetail grooves at the rear end of the top of the receiver. The rear-sight base is further positioned by the rear-sight base-spring screw (96). The rear-sight leaf (104) is pivoted at the rear of the rear-sight base, its operation being controlled by. the rear-sight base spring (95). The rear-sight slide (99) and rear-sight slide catch (100) operate up and down on the rear-sight leaf in such a way as to give a range adjustment of from 100 to 1,600 yards. The leaf is also provided with a battle sight. The ejection opening is located on the right side of the receiver, as is the hammer pin hole. The hammer pin hole is located so as to allow the disassembling of the hammer pin and subsequent parts. The left side of the receiver is provided with a guide for the operating handle (88). The operating handle is fitted with the operating handle plunger (89) which is held in place by the operating handle plunger pin (90), and which is operated by the operating handle plunger spring (91) in such a way as to retain the operating handle in the forward position unless force is applied to move it toward the rear. The bolt guide (72) is held in the side of the receiver above the operating handle by the bolt guide spring (73), which is attached to the inside of the receiver. The edge of the bolt guide projects inside the receiver forming a support for the bolt (75) when it is in the rear position. The change lever stop (20) is also assembled to the left side of the receiver, this part being held in place by the change lever stop spring (21), which is pinned to the inside of the receiver. The bolt support, right (3) and bolt support, left (4), are riveted to the inside of the receiver by means of three bolt support rivets (5) each, in such a way as to support the bolt (75) when it is in its forward position. |