add partial GunComponent with drop chance,

make FireOnDropSystem shared,
use drop chance per component instead of a hardcoded value

Content.Shared/SimpleStation14/Weapons/Ranged/Components/GunComponent.cs

@@ -0,0 +1,8 @@
+// ReSharper disable once CheckNamespace // Extending the GunComponent to add a variable
+namespace Content.Shared.Weapons.Ranged.Components;
+
+public partial class GunComponent
+{
+    [DataField, ViewVariables(VVAccess.ReadWrite)]
+    public float FireOnDropChance = 0.1f;
+}

Content.Shared/SimpleStation14/Weapons/Ranged/Systems/FireOnDropSystem.cs

@@ -0,0 +1,29 @@
+using Content.Shared.Throwing;
+using Content.Shared.Weapons.Ranged.Components;
+using Content.Shared.Weapons.Ranged.Systems;
+using Robust.Shared.Random;
+
+namespace Content.Shared.SimpleStation14.Weapons.Ranged.Systems;
+
+public sealed class FireOnDropSystem : EntitySystem
+{
+    [Dependency] private readonly SharedGunSystem _gun = default!;
+    [Dependency] private readonly IRobustRandom _random = default!;
+
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<GunComponent, LandEvent>(HandleLand);
+    }
+
+
+    private void HandleLand(EntityUid uid, GunComponent component, ref LandEvent args)
+    {
+        if (_random.Prob(component.FireOnDropChance))
+            // The gun fires itself (weird), with the target being its own position offset by its rotation as a point vector.
+            // The result being that it will always fire the direction that all gun sprites point in.
+            _gun.AttemptShoot(uid, uid, component, Transform(uid).Coordinates.Offset(Transform(uid).LocalRotation.ToVec()));
+    }
+}