g. The following table is only approximate and the limits will vary under different weather conditions. It is observed that at the rate of 40 shots per minute the gun did not become hot enough to cause keyholing. At the end of 22 minutes, the gun was functioning perfectly and the groups were approximately the same size as after 800 rounds. This table is not the result of one firing but has been checked by data of all firing for 2 years at The Infantry School. h. The following rates per minute were obtained by the firing and may be taken as standard. The rates per minute in automatic fire will vary according to the skill in changing magazines. (1) Semiautomatic fire: 40 to 60 rounds per minute. (2) Automatic, bursts of 5: About 100 rounds per minute. (3) Automatic, bursts of 10: About 120 rounds per minute. (4) Automatic, bursts of 20: About 140 to 160 rounds per minute. 90. Automatic fire.-a. Automatic fire is delivered in bursts of from 3 to 5 shots with one squeeze of the trigger for each burst, without reaiming between shots. Use of automatic fire is exceptional, since it is inaccurate even at close ranges, hard on the rifle due to the excessive heat and vibration, and a waste of ammunition. Its only advantage is the effect on the morale of friendly troops and that of the enemy. b. The dispersion of the Browning automatic rifle when fired automatically in bursts varies vertically from 8 to 10 mils and horizontally from 12 to 15 mils. These figures are dependent upon the length of the bursts fired and the steadiness of the holding. 91. Semiautomatic fire.-a. Semiautomatic fire is delivered at the rate of one shot for each squeeze of the trigger, each shot being an aimed shot. This kind of fire includes nearly all fire delivered by the automatic rifle. It is more accurate, consumes less ammunition, and is easier on the rifle than automatic fire. A welltrained automatic rifleman can, if necessary, deliver practically the same volume of fire with a semiautomatic as with automatic fire. However, the rate of 40 to 60 rounds per minute is considered the best. One hundred and ten aimed shots in 1 minute semiautomatic fire and 160 unaimed shots (assault fire) semiautomatic have been attained with 20-round magazines, but are not to be considered, except for use in emergencies and for a very short time. b. The dispersion of the Browning automatic rifle fired semiautomatically (single shots) is practically the same as that of the rifle. When fired automatically (in bursts), the vertical dispersion is from two to four times, and the horizontal dispersion from five to seven times, that of the rifle. 92. Fire characteristics.-a. Enumeration.—(1) The automatic rifle is capable of the rapid production of a large volume of fire. (2) It is able to deliver fire from any of the positions ordinarily used by the rifle man. (3) It has practically the mobility, visibility, and vulnerability of one service rifle, together with the fire power of several. (4) Its cone of fire is deep and narrow when fired semiautomatically. (5) Its fire is easily controlled and directed. (6) Due to the lack of a stable mount, it is not suitable for overhead fire or indirect laying. (7) It is not capable of sustaining fire as long as the machine gun. (8) It is liable to accidental cessation of fire. (9) It can act only by means of fire power. b. Deductions.—(1) The fire of the automatic rifle will equal the fire of several rifles for all ordinary firing. For fire on special targets, such as at a dense target or enfilade fire, its fire will be as effective as a much greater number of rifles. Because of this, the automatic rifle is the most valuable fire weapon in the squad. It is accordingly necessary to have all men of the squad thoroughly trained in its use, so that it can be kept in action as long as possible. (2) No emplacements are necessary and firing positions can be changed as often as necessary. (3) It makes a very indistinct target, hard to locate and harder yet to hit. If semiautomatic fire is habitually employed, the location of the automatic rifle will not be revealed by the noise of the firing. Because of its mobility, it can accompany the squad at all times. (4) Because of the nature of its cone of fire, flank fire upon a linear target is always desirable. (5) Its fire can be shifted in any direction with a minimum loss of time. It is fired by one man and consequently is much more easily controlled than several rifles in the hands of several men. (6) Because of its unfitness for overhead fire and indirect laying, automatic rifles should not be assigned to such work. (7) Since the automatic rifle is not able to deliver sustained fire, training will insure that its volume of fire is no more than the target presented may require. (8) The men in the squad should be fully trained to reduce stoppages and to keep the gun in action as long as possible. 93. Employment.-a. Position.-The automatic rifle is an integral part of the squad equipment and its place is with the squad. In rushes, it advances with the squad. In one man rushes, or infiltration, where a firing line is being built on the line of scouts, the automatic rifleman is the first man to join the scouts. b. Tactics. Being an integral part of the squad, the tactics of the squad are the tactics of the automatic rifle. However, there are certain times when the automatic rifle may be used to good advantage on some special mission, allowing the remainder of the squad to concentrate on other work. The above must not be construed to mean that the automatic rifle is separated from the squad-it is merely easier to control and shift the fire of one man than of several. The following list covers some of the special duties in which the automatic rifle may be of great value: (1) Engaging enemy machine guns or automatic rifles. (2) Dealing with attacks from the flanks. (3) Building up a firing line. (4) Being pushed forward to deliver flank fire, or to deal with menacing enemy agents. (5) Covering the advance of the rest of the squad. (6) Holding narrow defiles or from any narrow frontage from which it is necessary to deliver a large volume of fire. (7) Covering dead ground in bands of machine-gun fire. (8) Accompanying small patrols. (9) Strengthening outguards and detached posts. c. Coordination.-The automatic rifle is an integral part of the squad and its employment is governed according to the requirements of the squad. To separate a group of automatic rifles from their squads for segregated employment is rarely permitted. d. Detailed employment.-Detailed instructions for the employment of the automatic rifle in combat are given in TR 420-105. Section IX ADVICE TO OFFICERS IN CHARGE OF AUTOMATIC RIFLE INSTRUCTION. 94. Provisions not mandatory. The provisions of this section are not mandatory, but are given as a guide. 95. Preparation of schedules.-a. The preparation of a schedule for a course of automatic rifle instruction involves consideration of certain elements- (1) Time available. (2) Size of class. (3) Number of trained assistants. (4) Facilities-quantity of equipment, number of firing points available, weather probabilities. (5) Extent of course-whether or not it is to include record firing of Course A or less. b. In the schedule of instruction given below it is assumed that— (1) It is desired to fire Course A for record. (2) Trained assistant instructors are available in the ratio of one to each eight men firing the course. (3) Automatic rifles, accessories, and training apparatus are avilable in the ratio of one per four men. (4) Suitable classrooms and training areas are available. (5) Firing points are available in the ratio of one per four men. (6) The class firing does not furnish pit details. (7) No time is lost on account of rain, details, etc. c. It will be noticed that the course has two natural divisions: The first covering such instruction as necessarily precedes any known distance range practice; the second being the known distance range practice itself, The relative amount of time to be given each part of the first division is expressed as a per cent of the whole time allowed for the first division; also in number of hours of an ideal allowance under ideal conditions of 28 hours. The second division, known distance range practice, Course A, should receive at least 70 hours actually on the range. Per d. Schedule. Hours. centage. (1) Introduction and outline of course, organization. (5) Functioning.... (6) Stoppage and immediate action.. (10) Immediate action firing and 1,000-inch range practice. Total.. 28 100.0 (11) Known distance range practice.. 70 96. Methods of instruction for mechanical training.—a. When trained assistant instructors are available. The following method of instruction is suggested when trained assistant instructors are available: (1) Commissioned instructor in charge. (2) Assistant instructor with each group. (3) Instructor makes brief talk leading to particular subject. (4) Instructor explains work, imitated by assistant instructor. (5) Each member of group imitates. (6) Other members of group check the one doing the work. (7) Assistant instructors supervise. b. When trained assistant instructors are not available.-When the instructor in charge is unable to obtain trained assistant instructors, the following method is suggested: (1) Commissioned instructor in charge. (2) Instructor makes brief talk leading to particular subject. (3) Instructor demonstrates and explains work. (4) Instructor demonstrates work with one member of each group imitating him. (5) Each member of group imitates. (6) Other members of group check the one doing the work. 97. Mechanical training.-The object of mechanical training is as stated in paragraph 10. Too much stress should not be laid upon minutiae during instruction in the mechanics of the weapon. The object should be always borne in mind. 98. Preparatory range training.—Any tendency to slight this phase of instruction should be carefully avoided. This is an important phase in automatic rifle marksmanship instruction. Section III includes only such exercises as are deemed essential, taking into consideration the fact that the soldier has previously had a thorough course in rifle marksmanship. 99. 1,000-inch range practice.-a. A soldier who commences firing with the automatic rifle without the necessary preliminary instruction is almost certain to be a poor shot. Therefore, the provisions of paragraph 40 should be insisted upon. That paragraph provides that no soldier will fire the 1,000-inch course without previously having completed- (1) A thorough course in rifle marksmanship, (2) Mechanical training, and (3) Preparatory range practice.. |