The entrance hole on Chen's shirt is 2.4 cm long, 240% the length of the lead bullet. In experiments by Dr. Y's group, using lead bullets 1.0 cm long, same as the lead bullet in the March 19 shooting, with an impact velocity between 180 m/sec and 200 m/sec, the maximal length of any bullet hole produced on the shirt fabric was 1.5 cm. Since the target fabric was placed close to the muzzle of the acceleration tube, the maximal length of bullet hole on the shirt fabric that can be produced by a 1 cm long lead bullet launched 5 meters away should be shorter.60
Conclusion: The length of the bullet entrance hole on Chen's shirt is almost twice as long as what one can obtain in impact experiments using the same fabric as target.