Page 18 - Сигурност и отбрана - брой 2 - 2023

Сигурност и отбрана, брой 2, 2023 г. Научно списание

The dispersion of bullets when firing with the same weapon in
practically the same conditions is a natural phenomenon, which is called
dispersion of the trajectories of the projectiles as they move through the air.
The most reliable indicator of the scale of dispersion is the values of the
average deviation (σ) of the perforations relative to the dispersion axes that
run horizontally and vertically through the CPI. According to the applied
methodology, the shooting accuracy is determined by the values of the
average deviation from the dispersion axes (σ). The closer σ is to zero, the
greater the shooting accuracy.
The dispersion axes generated after processing the results of all series
in both groups are depicted as dashed lines in Figure 3.
The measurement of each deviation from the dispersion axes are in
absolute values. In the first series of the first group, the magnitude of the
average deviation relative to the X-axis ( ) is calculated after substitution
1
in Formula 2 with the measured values, as shown:

2
2
2
2
2
2
2
| + + ⋯ + | 5,5 + 5 + 2 + 28 + 19 2
= 0,67 √ 1 2 = 0,67√ = 11,57
1
− 1 5 − 1

This calculation is performed the same way with the values of the
measured deviation from the Y-axis ( ). The process is repeated for all
1
series of both groups. The summarized results are presented in Table 3 and
are graphically depicted in Figure 4.

Table 3. Mean deviation values relative to the dispersion axes.

First group – shooting with a Second group – shooting without a
contactless suppressor. contactless suppressor.
Series Series

1/1 11,57 6,81 1/2 10,35 3,11
2/1 9,54 15,22 2/2 14,00 7,42
3/1 15,71 14,76 3/2 11,15 16,71
4/1 12,57 20,08 4/2 22,52 9,42

5/1 16,94 6,41 5/2 17,68 8,74

Average 13,27 12,66 Average 15,14 9,08

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