James Park
14-05-2005, 12:59 PM
In obtaining sight settings, how accurate do you need to be?
My reasoning is as follows:
First, I definitely want to hit the 10 ring (in Target) or the 5 ring (in Field) first shot at a new distance (presuming of course that I shoot the arrow properly).
In field archery this is a critical requirement. For example, if I am to be competitive in the Men's Compound division I will need to shoot around 355 for a FITA Field round. Otherwise there are sufficient people who will beat me (Clint, Zoran, Pat, Brian, Leigh and Bryce, just to name a few). Working on the basis that at most I can afford to drop about 5 points, and recognising that I will probably shoot a few poor shots and may lose a few points through making errors in the allowance for slopes, I simply cannot afford to lose any additional points through having poor sight settings. Simply stated: if I come up to a new distance, set my sight correctly, and shoot the shot properly, I must be certain that I will get a 5. Otherwise I will be fairly certain not to win.
For target archery, I probably have the luxury of being able to shoot a 9 first arrow at the longer distances, but for any short range competition a 9 will probably cause me to drop behind the opposition. (It certainly did at this year's Archery Victoria Short Range Championships where I averaged 58 at 40M on the 80cm face and lost one point per end to Bryce).
If I must be assured that my sight settings are going to be good enough to have me get the maximum score first shot, they probably need to be sufficiently accurate to get me about half way into that ring, on average. That is, about to the edge of the X ring. That then allows a little room for for any mis-aim or technique error.
The error permitted in the sight setting can then be easily calculated using similar triangles. It will be: (the allowable error on the target) multiplied by (the peep to sight distance) divided by (the distance to the target).
For FITA Field:
The most demanding sight setting is the 20cm target at 20M. Here, my sight setting will need to be accurate to 0.4mm or better.
For FITA Target:
Allowing for the fact that at 90M we get a practice end, the most demanding sight setting is the 80cm target at 50M. Here, my sight setting needs to be accurate to 0.3mm or better.
How do we then do it?
My experience is that to get sight settings of the required accuracy by shooting each distance and marking the sight bar with a pen, or writing down each setting on a piece of paper will definitely not get you that level of accuracy. Also, the pen marks will be wide and probably not straight, and it is difficult to set the sight to them with the required accuracy.
I have found that it is essential to use a calculated set of sight settings from a program such as Accurate Sights (and others do a similar job).
These programs usually work by taking two very accurate settings plus a few measured parameters to calculate the other settings, using the modelled arrow trajectory. They can do this very accurately indeed (certainly Accurate Sights does so).
An important point to note here, is that the calculations are only as good as the input data. Hence, you need to ensure that those two sight settings are truly accurate. If we want to meet the requirements about, they need to be sufficiently accurate to get an X at each of the two distances. We can then be confident that the computer generated settings will be of sufficient accuracy for each of the other distances.
My reasoning is as follows:
First, I definitely want to hit the 10 ring (in Target) or the 5 ring (in Field) first shot at a new distance (presuming of course that I shoot the arrow properly).
In field archery this is a critical requirement. For example, if I am to be competitive in the Men's Compound division I will need to shoot around 355 for a FITA Field round. Otherwise there are sufficient people who will beat me (Clint, Zoran, Pat, Brian, Leigh and Bryce, just to name a few). Working on the basis that at most I can afford to drop about 5 points, and recognising that I will probably shoot a few poor shots and may lose a few points through making errors in the allowance for slopes, I simply cannot afford to lose any additional points through having poor sight settings. Simply stated: if I come up to a new distance, set my sight correctly, and shoot the shot properly, I must be certain that I will get a 5. Otherwise I will be fairly certain not to win.
For target archery, I probably have the luxury of being able to shoot a 9 first arrow at the longer distances, but for any short range competition a 9 will probably cause me to drop behind the opposition. (It certainly did at this year's Archery Victoria Short Range Championships where I averaged 58 at 40M on the 80cm face and lost one point per end to Bryce).
If I must be assured that my sight settings are going to be good enough to have me get the maximum score first shot, they probably need to be sufficiently accurate to get me about half way into that ring, on average. That is, about to the edge of the X ring. That then allows a little room for for any mis-aim or technique error.
The error permitted in the sight setting can then be easily calculated using similar triangles. It will be: (the allowable error on the target) multiplied by (the peep to sight distance) divided by (the distance to the target).
For FITA Field:
The most demanding sight setting is the 20cm target at 20M. Here, my sight setting will need to be accurate to 0.4mm or better.
For FITA Target:
Allowing for the fact that at 90M we get a practice end, the most demanding sight setting is the 80cm target at 50M. Here, my sight setting needs to be accurate to 0.3mm or better.
How do we then do it?
My experience is that to get sight settings of the required accuracy by shooting each distance and marking the sight bar with a pen, or writing down each setting on a piece of paper will definitely not get you that level of accuracy. Also, the pen marks will be wide and probably not straight, and it is difficult to set the sight to them with the required accuracy.
I have found that it is essential to use a calculated set of sight settings from a program such as Accurate Sights (and others do a similar job).
These programs usually work by taking two very accurate settings plus a few measured parameters to calculate the other settings, using the modelled arrow trajectory. They can do this very accurately indeed (certainly Accurate Sights does so).
An important point to note here, is that the calculations are only as good as the input data. Hence, you need to ensure that those two sight settings are truly accurate. If we want to meet the requirements about, they need to be sufficiently accurate to get an X at each of the two distances. We can then be confident that the computer generated settings will be of sufficient accuracy for each of the other distances.