1951: Chapter 1 – The Gun and Tripod – The Vickers Machine Gun

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Lesson 1. – GENERAL DESCRIPTION

A INSTRUCTORS NOTES

Aim

1. To introduce the weapon to the soldier and to give him a general idea of how it works.

Class and instructors

2. Squads under squad instructors. Squad seated in a semi-circle on right side of gun.

Periods

3. One 45-minute period.

Stores

4. Gun, tripod, ammunition liner, belt with drill cartridges, spares parts case, condenser can and tube, gun chest, spare barrel, cleaning rod and blast deflector.

5. Skeleton gun and wall diagrams are of value if obtainable.

Preparation

6. Gun mounted, and all accessories laid out in their correct place. If two guns are available, one should be stripped and the recoiling portions assembled on a table, the gun casing being fitted into the gun chest. Paras 13 and 14 will then not apply.

B CONDUCT OF LESSON

Approach

7. Give the aim of the lesson (para 1 above).

8. Explain that during the lesson the main parts of the gun and their names will be pointed out, but that it is not expected that they should be remembered in this first lesson.

The gun

9. Name. – .303-inch Vickers medium machine gun.

10. Weight. – 40 lb (with water in barrel casing).

11. Rate of fire. – about 500 rounds per minute.

Forces which work the gun

12. Describe how the gun is worked by two opposing forces:–

(a) The explosion of the charge in the round which drives the recoiling portions back, and

(b) The fusee spring, which forces the recoiling portions forward again.

Parts affected by recoil

13. Strip the gun to show the parts affected by the recoil. Show how they fit together by assembling them on a table. Emphasize the strength of all parts. The parts affected by recoil are:–

Muzzle cup.

Barrel.

Right and left side plates.

Crank and crank handle.

Fusee and spring.

Connecting rod.

Lock.

Parts of the feed-block.

14. Reassemble the gun before continuing the lesson.

The barrel casing

15. Describe the outside of the barrel casing, pointing out the following parts:–

Muzzle attachment.

Blast deflector.

Screwed plugs for filling and emptying.

Adaptor for condenser tube and cork plug.

Foresight.

Water-cooling system

16. Explain that inside the barrel casing are the barrel and steam tubes. Use the diagrams and skeleton gun to show these to the squad.

17. Point out that the barrel is surrounded by water to keep it cool. Explain that the firing of the gun will heat the barrel which in turn heats the water and after firing about 500 rounds rapid the water will boil and give off steam.

18. Describe how the steam escapes from the barrel casing by means of the front or rear hole in the steam tube depending on the position of the sliding valve. Show, using diagrams or a skeleton gun how, when the gun is fired with elevation, the valve covers the rear hole and allows the steam to escape through the front hole. Similarly when the gun is fired with depression the valve covers the front hole and steam can escape through the rear hole.

19. Describe how the steam is carried from the steam tube, through the steam escape tube and then through the condenser tube into the condenser can. Explain that in order to condense steam into water again, the can must be about two-thirds full of water and the end of the condenser tube below the level of the water. If the end of the condenser tube is above the level of the water, the steam will escape into the air and water will thus be lost.

Breech casing

20. Point out the following parts of the breech casing:–

Outside plates.

Bottom plates.

Front and rear covers.

Rear crosspiece.

Left side of casing:–

Front cover catch.

Fusee spring and box.

Dial sight bracket.

Left slide.

Right side of casing:–

Check lever.

Right slide.

Collar and roller.

Rear cover:–

Tangent sight.

Bottom plate:–

Sliding shutter.

Rear crosspiece:–

Traversing handles.

Safety catch.

Thumb-piece.

Firing lever.

Show how the rear crosspiece is held in position by the fixing pin.

Feed

21. Explain that the gun is fed by a belt containing 250 rounds which passes through the feed-block from right to left.

Tripod

22. Point out and name the parts of the tripod:–

Legs and jamming handles.

Cross-head and pivot.

Socket.

Traversing clamp.

Direction dial.

Elevating gear.

23. Demonstrate clamping up of the legs.

24. Show method of fixing the gun to the tripod by the cross-head and elevating joint pins.

25. Demonstrate that the gun is elevated or depressed by the elevating gear and that the traversing clamp, when tightened, controls the traverse of the gun. Demonstrate that by loosening the traversing clamp fully the crosshead can be removed from the socket. Show the pivot.

The weight of the tripod is about 50 lb.

Gun chest

26. Tell the squad that in transit, the gun is placed in the gun chest. Show how this is done and how the cleaning rod and spare barrel fit in the chest. When the gun is in the chest, the blast deflector is usually put on the strap of the spare parts case.

Conclusion

27. Demonstrate and explain the correct sitting position behind the gun, knees bent and out, heels together, elbows resting inside the thighs, first fingers over the top of the traversing handles, second fingers under the safety catch and third and little fingers around the base of the traversing handles. The thumbs resting lightly on the thumb-piece and the firer looking to the front. Demonstrate loading, firing and unloading. Explain that the squad will be taught these actions later, and they are only being shown for interest sake.

28. Questions to and from the squad. Don’t expect the squad to remember the names of all parts. In answering questions the instructor should be careful not to get involved in the subject matter of subsequent lessons.

29. Sum up the main points.

Lesson 2. – CHARACTERISTICS

A INSTRUCTORS NOTES

Aim

1. To teach the class the capabilities and limitations of the MMG.

Class and instructors

2. Class under and officer. Squad instructors will be required at the conclusion of the lesson to coach their squads in firing practice 1, Part 1, MMG course.

Periods

3. One 45-minute period for lecture.
One 45-minute period for demonstration.
The time required for firing the range practice depends on the size of 30-yards range available and the number of guns available and the number of guns that can be fired simultaneously. Five minutes per man per gun can be taken as a guide.

Stores

4. For lecture.– Gun, tripod, dial sight, condenser can and tube, blast deflector, belt and liner, range-finder, director and stand.

5. For demonstration.–Service gun and tripod and one spare in case of major breakdown. Spare parts case and box. DP tripod. White screen and 3 wooden plates. Dry ashes and wet sack.

6. For Practice 1.– As many service guns, complete with stores, as the size of the range permits. 50 rounds SAA per man – spaced in two groups of 25 rounds.

Preparation and rehearsal

7. Two instructors will be required to give the demonstration. The supervising officer should rehearse the demonstration with them beforehand.

8. Service guns must be carefully prepared and all belts should be inspected.

B CONDUCT OF LESSON

Approach

9. State the aim of the lesson (see para 1 above) emphasizing that unless machine-gunners know what the gun can do and what it cannot do, it will not be employed in the most efficient way.

Concentrated fire

10. Explain that the first characteristic of the gun is its ability to produce concentrated fire – it can put a number of bullets into a small space. This is due to its fixed mounting and close grouping.

Volume of fire

11. Explain that the high volume of fire is due to the belt feed, and that the volume is controlled by the length of burst and rate of fire. A burst is always 25 rounds.

Rates of fire

12. Normal.– Pause of 8 seconds between bursts.
Rapid.– Pause of 2 seconds between bursts.

Accurate fire

13. State that the great accuracy of the gun is due to the fixed mounting and to the use of instruments, eg, the range-finder.

14. Tell the squad that accuracy can be maintained in darkness, fog or smoke by means of special instruments.

15. Due to its accuracy and to the instruments provided, the gun is able to fire:–

(a) Over the heads of the infantry.

(b) Indirect (explain briefly what this means).

(c) Blinded by smoke or fog.

(d) By night, if daylight preparations have been made.

Sustained fire

16. Explain that the gun can maintain the high volume of fire for long periods due to its strong mechanism, belt feeding and water cooling.

Long range

17. The maximum range of the gun is 4,500 yards, but it is not normally required to fire over 2,000 yards. It can engage targets well beyond the reach of other low trajectory weapons.

Flexibility

18. Having 360 degrees traverse, the gun can engage targets in rapid succession over a wide area. Emphasize that flexibility depends to a large extent on good indication and recognition of targets.

Mobility

19. State that the gun and its team are carried in a tracked carrier giving a good cross-country performance, and some armoured protection against small arms fire.

Under certain circumstances, the gun can be fired from the carrier.

Limitations

20. Describe the limitations of the gun and the means of remedying or minimizing them as given below:–

(a) Mechanical breakdown – good maintenance and handling.

(b) The following points may enable the enemy to detect the position of a machine gun:–

Steam – use of condenser can.

Smoke – avoid excessive oil.

Muzzle blast – use of blast deflector and wet sandbags, etc.

Flash – screen from flanks.

(c) Weight of the gun and tripod is a limitation as regards manhandling.

Demonstration of characteristics

21. Throughout the demonstration the supervising officer should give a commentary on the main lessons to be learned. He should use the demonstration to drive home the points he made in his lecture.

22. Sequence of the demonstration and notes on its conduct are given below:–

Demonstrate:–	Method:–	Points to emphasize:–
1. Service burst.	Fired at stop-butt. Belt spaced.	Importance of service burst and time to fire.
2. Rates of fire. (a) Normal.	Belt not spaced. Fired at stop-butt.	Time for maintenance between bursts.
(b) Rapid.	Belt not spaced. Fired at stop-butt.	Time only for quick check of aim between bursts.
3. Volume and accuracy.	100 rounds straight at screen.	Size of group and volume of fire.
4. Factors affecting accuracy. (a) Tripod not stamped in.	100 rounds at screen.	Compare size of group in each case.
(b) Tripod stamped in.	100 rounds at screen.
(c) Loose jamming bolt.	Prepare tripod by loosening jamming bolt and tumbler nut. 50 rounds straight at screen.
(d) Punch fired.	50 rounds straight at screen.	Emphasize that human element does not affect accuracy.
(e) Recruit fired.	50 rounds straight at screen. Gun to be laid and loaded by instructor.	Emphasize that human element does not affect accuracy.
5. Flexibility (a) Rapid engagement of targets.	3 coloured plates on stop-butts, sufficiently spaced to necessitate the use of the clamp in one switch.	Speed with which targets can be engaged.
(b) Swinging traverse.	1 belt along stop-butts Condenser tube to be removed from can to show amount of steam given off.	Used in an emergency only. Rate of traverse 1 yd in 2 secs at 25 yds.
6. Muzzle blast. (a) Ashes down, blast deflector off.	2 spaced bursts.	Compare amount of dust caused by blast.
(b) Wet sacks down.	2 spaced bursts.
(c) Blast deflector, no wet sacks.	2 spaced bursts.