‘The 590 Rule’: Field Firing Range Safety

The way I was brought up in the British Army, and a method of training that I took with me to my time in Iraq and Afghanistan, is that field firing exercises are not run as set-piece exercises with dry and blank run-throughs, but rather as ‘sight unseen’ tactical live firing exercises.

I came across the US Army method when on my first exchange trip to Fort Bragg in the ’90s. We were running through some drills to practise trench assaults and we went through the scenario dry day and night, blank day and night, and finally live firing day and night. So by the time we came to the night fire we were all rehearsed and new exactly where to be. It was new thing for us.

I used to run a training program for PARA recruits and as the platoon leader I was responsible for the creation of the tactical exercises using the allocated field firing ranges. It was the same way back in battalion with trained soldiers. As a qualified Stage 5 Range Conducting Officer I would plan the range depending on my objective and ensuring that all enemy positionss could be assaulted while within the ‘arcs of fire’ allocated to the range. This limited unrealistic ‘check fires’ for those firing out of arc.

The difference between running recruits and trained soldiers through the ranges was the number of allocated safety staff and also the role of the squad leaders. For recruit training, the squad leaders were part of my training cadre and as such I would walk them through the range, showing them the planned positions for each assault. For fire team, squad and platoon attacks I would always try and plan it so that each squad had two objectives, usually bunkers, which would mean that each team would have a bunker to assault, going to a flank using ground to do so. For a platoon  attack we would run through six enemy bunkers, each team doing its own assault, wth the bunkers set up in such a way that the other teams/squads could provide fire support throughout. The bunkers would be grenaded. For recruits, we had the squad leaders see the range so that they could mechanically run the recruits through the techniques of the assault for the best learning experience.

For trained soldiers, the range would be a tactical problem which required leadership to solve, and that was part of the training benefit. It would only be manged in so much to prevent the commander taking his squad too far outside the limitations of the range, and thus being unable to fire.

Safety was provided by safety staff wearing day-glo vests. They would stand at the edge of a formation that was assaulting, for instance, in order to allow the fire supporting groups safety to best see where the friendlies were and make sure fire was switched according to the safety rules. Usually, you would have one ssfety allocated to each fire team of four. They would be behind the team and watch as the range went on.

As a rough safety rule, we had the ‘590 Rule’. This refers to 590 mils. Mils is a military compass measurement that is used instead of degrees. There are 6400 mils in a circle, just like there are 360 degrees.

The 590 rule stated that effectively, standing behing one firer(s), another group ahead of them could not be within an angle of 590 mils, or the rear group would have to check or switch fire.

The way it was done in the rough: Imagine standing and holding both fists out in front of you at arms length. Put both thumbs up. Rotate your fists knuckles up so that your two extended thumbs touch each other. Now pop up your two little fingers. You now have some crazy gang sign/spock thing. For example, put the right little finger on the guy on your right. The guy on the left has just bounded forward and the guy on your right is to his rear providing fire support. Is the guy on the left within the left little finger? If so, he is within 590 mils and you need to check fire the rear guy on the right. Clear as mud?

This is a rough technique that can be used to make sure fire does not get too close to those ahead of the firer, when conducting your own live firing training. Once you get to some high speed training and out on operations, its big boys rules then. Just remember, don’t shoot your buddy, watch for muzzle clearance over cover, and if you get closely ahead of the muzzle of a firing weapon it will hurt your ears like hell.

An example of how the rules went out the window for operational training: fire support would go into a bunker all the way until the grenadier reached the bunker and was preparing his grenade. As he went to post it into the bunker, fire would switch away from him. This requires good shooting and trust. But it suppresses that bunker until the last second.