diff --git a/src/l3/r4/r4.c b/src/l3/r4/r4.c
index ce44e8e..f81f336 100644
--- a/src/l3/r4/r4.c
+++ b/src/l3/r4/r4.c
@@ -129,16 +129,8 @@ void physics_update(R4BetaState* st, float t){
  * m2 is the mass of bullet. `v` is the speed of bullet */
 void RigidBodyState_when_shot(RigidBodyState* self, vec3 imp, float m2, vec3 v){
     vec3 IO = vec3_minus(imp);
-    float IO_norm_sq = vec3_dot(IO, IO);
 
-    vec3 linear_speed_gain;
-    if (IO_norm_sq < 0.00001f) {
-        linear_speed_gain = v;
-    } else {
-        vec3 v_projected = vec3_mul_scal(IO, vec3_dot(IO, v) / IO_norm_sq);
-        linear_speed_gain = vec3_mul_scal(v_projected, m2 / self->p.mass);
-    }
-    self->speed = vec3_add_vec3(self->speed, linear_speed_gain);
+    self->speed = vec3_add_vec3(self->speed, vec3_mul_scal(v, m2 / self->p.mass));
 
 
     vec3 www = vec3_mul_scal(vec3_cross(v, IO), m2);