The video tape employed has a speed of 30 frames per second. The projectile used was a Federal .45 caliber 230 grain bullet, and was traveling at approximately 850 feet per second. This means the pattern is created in its entirety in less than 1 second. The faster the velocity of the projectile, the more quickly the resulting pattern is created. However, the blood does not travel at the same speed as the projectile.
Blood is projected back towards the shooter through the entry wound.
The amount of blood used in the sponge does not affect the characteristics of the patterns created, but it does impact the diameter of the resulting pattern. The more blood used, the greater the diameter of the pattern. Regardless of the amount of blood used or the type or velocity of the projectile used, a consistent pattern with uniform characteristics are created. The video frames were carefully studied to determine what happens when a bullet strikes a bloody target. Even in the event of no exit through the bloody target, blood is projected back towards the shooter.