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Tuesday, July 15, 2008
In field Target we use the silhouette shape as target, while the 'hit' zone has a diameter of
40mm. A normal competition course consists of 10 targets set out at fixed ranges of
between 15 metres and 50 metres. One shot per target is allowed, with one point being awarded
if the target is successfully knocked over.
The skill in this type of shooting is in accurately judging the range of each target, and making
allowances for wind and weather conditions, which can change the path of the comparatively
slow and lightweight air rifle pellet.
Due to the movement created by breathing it is impossible to release an accurate shot without
holding the breath. However as soon as breathing is suspended the body’s functions begin to
deteriorate as oxygen starvation sets in. The eyes ability to function is the first to go
followed by the muscles, which begin to contract. Not least there is a feeling that ‘I
must breathe, I must breathe….’ as the body tries to protect itself. All of which are not conducive
to firing a controlled shot. These effects can be avoided if breathing is suspended for only a
short period of time. This is around 10 seconds on an exhalation, slightly more on inhalation.
When breathing in, the chest muscles become tense, relaxing as you breath out. As we desire
to reduce tension in a shooting position it is therefore desirable to suspend breathing on
Whatever type of trigger or method of control, the desired outcome is the same, to release the
trigger without moving the gun from the point of aim. Any triggering method that brings about
this outcome consistently is acceptable.
All triggers need to be:
• Consistent - if the release point and pressure of the trigger is not the same for each shot
good control and release is impossible.
• Reliable - not only to ensure good performance but also from the safety perspective.
• Smooth in operation.
• Can be operated with reasonably light pressures.
It is also desirable if they are:
• Adjustable for weight.
• Adjustable for position of the blade.
• Easy to adjust.
Types of trigger
Although there are 4 main types of trigger, only 2 have found general acceptance in field target
shooting. These are the single and two stage trigger systems.
Single Stage - This type, has no free movement prior to release. This means that the sear engagement has to be quite shallow if the trigger is to have acceptably low creep. This in turn means that the triggers of this type have been set at higher weight levels than the two-stage variety.
Two Stage - This type has a degree of movement before a further resistance is felt. Further
movement beyond this point will release the mechanism. The two-stage trigger has deep sear
engagement, which is taken away as the first stage is taken up. Due to this these triggers
should be safer from accidental discharge. However the majority of two stage triggers are in fact
single stage with the free movement built into the trigger blade.
It could be assumed that, considering the desired outcome of releasing the trigger without
moving the gun, as light a trigger as possible would be an advantage since this introduces less
force into the system. However this is not always the case. An overriding factor is the shooters
ability to feel the point of release and control exactly the point at which the gun fires – not only
in training but also during a competition. For this reason the triggers on field target rifles
are rarely set on the minimum setting. Experimentation will find the ideal weight for an
individual shooter. The less expensive rifles may have non-adjustable triggers. These tend to be
set at rather high weights and can only be altered by a gunsmith.
Grip and Trigger Operation
The trigger hand must be placed such that it allows the trigger finger to pull the trigger blade
rearwards down the centreline of the rifle. There must be no tendency for the finger to push
the trigger blade to either the left or right. The hand must be positioned so that on releasing the trigger no lifting or pulling down on the rifle occurs.
The amount grip pressure is a matter of personal preference.
However one or two general rules apply:
• The right hand does not steer the rifle onto target.
• The grip must be consistent.
• Heavier triggers demand a firmer grip.
• The grip used on spring rifles is generally lighter.
As long as the thumb is not active during the trigger release i.e. changing it’s pressure on the gun
then any of the methods will be successful.
Methods of Operation
There have been many ways of describing the means of smoothly increasing the pressure
on the trigger until the gun fires. The classic ‘squeeze the trigger’ is perhaps the least
accurate. This gives the impression that the pressure is increased over the whole hand
squeezing the grip and trigger as a consequence. Nothing could be further from the truth. In
correct trigger release the only thing that moves is the trigger finger, the aim remains stable
and the gun fires without any extra movement being transmitted to it. However there are
several methods employed to bring about this action.
There are several mistakes that most often occur in trigger release:
• Snatching the trigger – that is a very rapid build up of pressure, made even worse if
the finger takes a ‘run at it’ i.e. approaches the trigger blade at speed.
• Pulling through the first stage quickly and hitting the second stage pressure and
• Taking up the first stage then releasing the pressure a little before snatching at the
All of the above will transmit large movements to the gun as it fires.
For a single stage trigger and a good hold the aim can be maintained and pressure increased until the gun fires. Alternatively, with a hold that is not as stable, the pressure is increased in stages, stopping the increase as the hold drifts away from the target area. Some shooters use a single stage trigger but the forefinger pulsates on the trigger blade before building up the pressure rapidly. This works on the principle that it is easier to complete a movement than to start one and cuts down the reaction time on the release.
For a two stage trigger and a good hold, the first stage is taken up boldly then the aim is refined and the pressure is increased steadily on the second stage until the gun fires. For a two stage trigger and a less stable hold, the first stage is taken up boldly then the pressure is increased in stages, stopping the increase as the hold drifts away from the target area. This method is similar to the pulsating method but is applied to a two-stage trigger. This involves boldly taking up the first stage and then the finger pulsates before rapidly building up pressure on the second stage.
The aiming and firing process does not end when the trigger is released. The process of
maintaining the aim during and beyond the release of the shot is called follow through.
Follow through is very important, particularly in air rifle shooting, because the action of the
air rifle is quite slow. It takes time for the shot to develop after the trigger is released. In a precharged rifle the trigger releases the hammer, which moves forward to open the valve, air is
released which accelerates the pellet up the barrel before it finally leaves the muzzle and only
then is it free of the influence of the shooter. During this period if the aim is disturbed a poor
shot will result.
There are several physiological reasons to follow through. When you see the correct sight
picture, you release the trigger but the finger doesn’t move instantly. A delay of some 0.3
seconds, which is equivalent to you reaction time, occurs before your finger moves. Through
this period the aim must be maintained.
Also, the gun is held in position by some muscular effort that must remain the same until the
shot has left the rifle. Without follow through there is the chance that the muscles holding the
gun might relax a fraction of a second early, before the pellet has left the muzzle, moving the
gun and resulting in a poor shot.
Good follow through can be obtained by maintaining the aim of the rifle for about 1 second after
trigger release. This is more than enough time to allow the shot to leave the rifle.
The other component of follow through is psychological. It is insufficient to physically maintain
the rifle in position whilst the shot is fired. Concentration on the execution of the shot must also
continue if the full benefits are to be gained. Continuing the attention on the movement of the
muzzle during the release valuable information is obtained on the quality of the shot. This is
referred to as ‘calling the shot’ and gives feed back on technique to be used for subsequent
shots. It is very useful when deciding when to make sight corrections as these can be based on
information from shots that you called as being technically good.