If Moses had been a machine-gunner, there would have been eight commandments instead of ten:
“Probably the most basic of all and one that we don’t have to spend much time discussing — MUTUAL SUPPORT. We just have to make sure that no gun is sitting out there in isolation. If possible, each gun should be sited where another gun can fire directly at it if it is overrun. This, of course, is seldom possible to achieve with every gun on the position. Some times you may have to fill in with a C2 or a couple of riflemen.”
“The second one is probably the most important — CO-ORDINATION OF FIRE. This starts with the proper preparation of range cards and the registration targets. The range card in a machine gun trench is much more important than the one used by a rifleman. There will be many occasions when the gunner won’t be able to observe the target area, but his fire will be essential. Each gun must have an FPF and four or five targets. As soon as the tripod is well bedded in, the T & E data for each of these targets must be recorded. That way the crew can engage any of their targets whether they can see them or not.”
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“Well, the third one is pretty basic — INTERLOCKING FIRE. This helps with your all round defense plus provides a high concentration of fire into your killing areas. It ties in closely with the next principle — SITED IN PAIRS. There will be times during the battle when you will want almost continuous fire on a target. Our guns are not capable of providing this; therefore, you have to use two guns firing alternate bursts. You must also always keep in mind that mother nature is a bitch and she always sides with the hidden flaw. A separated casing can occur at any time and having a stand-by gun might make the difference between a group of BMPs being destroyed or passing through a killing area unscathed. While we are talking about APCs, it’s a good idea to pair an HMG with a GPMG. A GPMG won’t hurt an APC and it’s a terrible waste to use C44 AP/T ammo against personnel, so neither gun can do the complete job by itself. Ideally, paired guns should be about 25 metres apart and work under one fire controller. Ground and distribution of guns within the company does not always allow this, however. If need be, two guns from different platoons can work together. The co-ordination problem becomes a bit of a monster, though.”
“The next two principles go hand in hand. They are — SITED IN DEFILADE and SITED TO PRODUCE ENFILADE FIRE. Defilade simply means that you have something solid between you and the bulk of the enemy’s direct fire weapons and enfilade means that you hit the enemy from a flank. As glamorous as it might sound, the last thing we want is to have the enemy staring down the muzzles of our machine guns. I can best illustrate this with a diagram.”
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“I mentioned the effectiveness of modern tank gunnery already and the enemy can also bring down a considerable weight of artillery, not to mention his close air support. PROTECTION AND CONCEALMENT is our seventh principle. Our guns must be well dug in, in proper machine gun trenches.”
“Yes,” I interrupted. “I’m familiar with machine gun trenches. Let’s get to the last principle.”
“ECONOMY,” he stated. “The standing joke on my course was that there were originally only seven principles and that economy was added as part of the Government’s latest austerity programme. When you look at it seriously, though, its as important as the other seven. Economy of ammunition is the important thing but we mustn’t disregard wear and tear on the guns. The HMG has a cyclic rate of close to 500 rounds per minute (RPM) and the GPMG can reach over 600. Both guns will fire at this rate of limited periods and can be used that way in an emergency. It doesn’t take long, however, before barrels burn out, oil burns off, metal parts expand and tolerances become just a little bit too tight. Then the gun will let you down, probably when you need it the most. The proper rates of fire for the HMG are 40 RPM normal and 100 RPM rapid. The GPMG is 60 and 90. We found on my advanced course, with the GPMG firing four to six round bursts, that a slow count of five between bursts would give normal rate while a three second pause would give rapid.”
“Ammunition expenditure is probably the biggest thing we will have to watch. I had a look through the carriers last night and we are well bombed up. I would say substantially higher than our official first line. That ammo is not doing us much good back in the zulu harbour, though. Firing rapid rate, an HMG goes through 35 pounds of ammo each minute and a GPMG uses about seven. That could add up to a tremendous resupply problem. One that might be impossible to cope with in the heat of battle. The solution is to dump as much ammo as we dare on the position itself. Then we must exercise extremely tight fire discipline. We can’t afford to have three guns firing at the same target if one will do the job. We shouldn’t waste HMG ammo on soft targets if there is a GPMG in range and available for the task. We have to be particularly stingy with our C44 AP/T.”