Page 15 - Сигурност и отбрана - брой 2 - 2023

Security & Defense, Issue 2, 2023 Scientific journal

Minimizing errors during shooting and creating approximately the same
conditions for each shot is essential for the reliability and objectivity of the
obtained results. This goal is achieved by conducting the shooting at a semi-
closed shooting range, which minimizes the impact of the effect of the
movement of air masses on the projectile.
Ensuring uniform placement of the target is achieved using screws
passing through the fixing points (+) depicted on the target and the openings
in the stand intended for that purpose. The target is placed at the specified
distance on the stand padded with extruded polystyrene with a bulk density
3
of 32 kg/m , which allows the projectile to pass through the target without
hindrance while at the same time preserving its structural integrity. This
results in limiting the tearing of the target upon contact with the projectile,
resulting in a precise reading of the firing result.
The uniform aiming of the submachine gun at the target is assisted by
the use of a single-point mount, limiting its displacement from the desired
position when firing. Verification of the target’s location relative to the
horizon of the weapon is carried out using a laser level.
Ammunition from a single batch is used when conducting the
experiment, which leads to a reduction in the differences in the ballistic
indicators of the projectile.
The practical aspect of the data collection consists of ten series divided
into two groups – five with and five without the contactless suppressor, each
series includes five rounds fired with the weapon platform in a single-shot
mode. Before firing the shots of each group, the barrel is warmed up with a
single shot that is not part of the series to ensure approximately the same
conditions for subsequent shots.
Before conducting the actual shooting, designed to determine the
grouping and accuracy of hits, two test series are conducted. Their purpose
is to check the hold of the weapon's mount, to confirm that the target is
secured on the stand, and to verify that all perforations are inside the target
borders. In these test series, the differences in the initial velocity of the
projectiles are measured, which is accomplished using a ballistic
3
chronograph .

3. PROCESSING AND ANALYSIS OF THE RESULTS
The results of the projectiles’ velocity measurements taken during the
two test series are shown in Table 1.
The results of the measurements show that on average the initial
velocity of the projectile is higher when the shots are fired with a contactless
suppressor. The higher velocity gives the projectile a flatter trajectory which

should improve accuracy on short distances.

3 Ballistic chronograph – a technical device used in shooting practice to measure the projectiles’ velocity.
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