Target Sports

TARGET RIFLE BASICS: SIGHTS SET ON PERFECTION

Created on 14th May 2009

CHRIS WHITE explains the importance of sighters and how to use them to best advantage

NOW WE understand the theory of grouping it ought to be obvious that two shots may or may not be representative of what is to follow. Since this is what we are stuck with under NRA rules we must make the best of it. The tighter the group produced by the shooter/rifle/ammunition combination the less likelihood there is for the next shot to be seriously damaging. On the face of it sighters may be regarded as just that. In fact sighters have a number of important functions of which sight setting is but one. They serve both to stabilise the rifle and the shooter as well as giving the shooter an insight into where the group centre may be. They then permit a sight adjustment to maximise the chance of the next shot, the first to count, being in the bullseye.

Finally they also help to calibrate our wind judgement; of which more soon. Experienced shooters will know that the first shot through a cold, clean barrel will not be in the centre of the group. In the case of my Barnard it will often be just under a minute low. The next shot is likely to be more realistic but if the barrel is squeaky clean this will also probably be low. (This is why Match Rifle shooters are allowed ‘blow-off' shots before their first shoot).

In the case of my smallbore rifle (Anschutz 1713 Supermatch) the first shot of the night will be really wild at 11 o'clock, particularly when the rifle has not been cleaned for a while. (We are not getting into the pros and cons of cleaning smallbore rifles at this stage). Now this is not a problem since I can shoot as many sighters as I like until I deem that the rifle has stabilised and any subsequent group will be representative. Not so when shooting TR.

While I would not advocate shooters having a sloppy attitude to firing sighters since they are, arguably, the most important shots of the match, they do afford the opportunity to settle in.

If we read the somewhat limited number of ‘how to shoot' books specifically directed at NRA Target Rifle, we will probably read the advice of shooting two straight sighters, plotting the mean elevation of these and setting our rearsight to this mean. That's fine so far. If our rifle puts its first shot into the centre of the group that's as far as it would need to go, but as we have just seen two sighters are not usually enough to guarantee stability of our group centre. Now we need to use our brains. Reference to our score book should tell us what we expect our corrected elevation to be for this type of ammunition at this distance and, hopefully on this range. (Target Sports December 2005 to February 2006). Study of our score book in general will tell us if we expect our sighters to be out of the group.

Taking all this into account we can then make our judgement on whether we make a ‘full correction' based on the mean of the two sighters. Let's illustrate this with an actual live example (see figure one). The venue, rifle and ammunition were all familiar territory therefore there could be a high level of confidence that the actual elevation would end up as 15½. Equally probable was that the first shot would be at least ¾ of a minute low and that the next one would be only a little higher.

When the first sighter went ½ minute high little thought was needed to reach the decision to come down ½ minute. The second sighter was on the waterline, both shots plotting to 15 minutes. Were it not for the experience that these would very likely prove to be at the bottom of the group the rearsight would have been left where it was, particularly given that it was already ½ minute down on expectation. This is the point where a balanced decision had to be made. Confident that the sighters were straight shots, I lowered the rearsight another ¼. After the shot was plotted the elevation graph showed this setting to be the current mean. Nevertheless there was still every reason to believe that the sighters would end up at the bottom of the group. Consequently I lowered the rearsight another ¼, at this point a full minute lower than the expected elevation. This cost a point albeit the next shot was at the top of the group.

The whole point of this is neither to illustrate that I can score a 49 nor that I can make a mistake but to make the point that these decisions are not as straightforward as we may have been led to believe. As always, the more experienced we are and the better we shoot the easier it is to make these decisions.

At this stage we need to come back to a point which has been made before and that is the ability to call a bad shot. In a Utopian world we would only fire straight shots but even Olympic class shooters occasionally make a mistake, for whatever reason. The ability to recognise the difference between good and bad shots elevates the club class shooter to County class. The ability to avoid letting bad shots off at all elevates the County class shooter to International level. Here we are getting ahead of ourselves because this series is about the basics. Nonetheless it is very important that if a sighter is less than perfect we acknowledge that and make our subsequent decisions accordingly. It is over 25 years since the late George Arnold uttered the immortal words: "One can no longer afford the luxury of making the first to count one's third sighter!"

Our smallbore brethren can shoot a lot of sighters if need be and make their decisions on where the centre of the ‘core' group is.

We do not have that facility and if one or both sighters are hooky shots we are in trouble from the start. Don't be fooled into thinking that because a sighter goes into the middle of the V-bull it has to be a good shot!

We have covered grouping and how our understanding of this allows us to use our sighters to best advantage but just before we leave the subject let's revisit the topic
of rearsights.

In the days when SR(b) rifles did well, with issued .303, to hold 2½ minute groups and 200yd bullseyes were themselves 2½ rifle minutes in diameter, sight adjustment increments of ½ minute were more than adequate. The 200yd bullseye is now 1¾ rifle minutes in diameter and the V-bull very little over 1 rifle minute. Good rifles and ammunition are capable of shooting ½ minute elevations in the right hands; ¼ minute adjustment is only just adequate to ensure that the group is properly centred. While European smallbore rifle sights are adjustable in mills, the minute equivalent on a modern rifle is likely to be no coarser that 1/10 of a minute and may be as fine as 1/20. BSA/Parker Hale were offering one eight minute sights at least 40 years ago. Next time: wind.

TARGET RIFLE BASICS: SIGHTS SET ON PERFECTION

Related Links

TARGET RIFLE BASICS: WINDS OF CHANGE

TARGET RIFLE BASICS PART TWO: SEARCHING FOR THE ONE

TARGET RIFLE BASICS PART ONE: SEARCHING FOR THE ONE

TARGET RIFLE BASICS PART THREE: TELL THEM WHAT YOU HAVE TOLD THEM

TARGET RIFLE BASICS PART TWO: TELL THEM WHAT YOU HAVE TOLD THEM

TARGET RIFLE BASICS: UNRESOLVED ISSUES

TARGET RIFLE BASICS: TELL THEM WHAT YOU HAVE TOLD THEM

TARGET RIFLE BASICS: A LEVEL PLAYING FIELD?

TARGET RIFLE BASICS: ZERO THE HERO

TARGET RIFLE BASICS: POSTIVELY NEGATIVE

Get a copy of Sporting Rifle

TARGET RIFLE BASICS: SIGHTS SET ON PERFECTION

Related Links

Newsletter