Page 24 - Shot In The Dark Bullet Striations
P. 24
Lab
Procedure
Lab 1:
Learning to look
at striations
1. Examine Bullet A with a magnifying glass or 4. On your data collection sheet, record the patterns
under a microscope at a very low magnification. you see. Describe, or draw, the marks observed,
Examine the striations on the fired bullet. paying close attention to the distance between
the striae and the length of each individual mark.
2. On your data collection sheet, record the Rotate the bullet and record the striations you
patterns you see. Describe, or draw, the see from another angle. Look for similarities and
marks observed, paying close attention to the differences between the two bullets.
distance between the striae and the length of
each individual mark. Rotate the bullet and 5. Place both bullets side by side under the
record the striations you see from another microscope or magnifying glass. Slide them
angle. Firearm examiners examine the entire back and forth and rotate them in attempt to
bullet, so be thorough in your observations. detect similarities between them.
3. Examine Bullet B with a magnifying glass or 6. In your group, determine whether the same gun
under a microscope at a very low magnification. fired these two bullets or if they were fired from
Examine the striations on the fired bullet. different guns.
24 THE MYSTERY OF LYLE AND LOUISE
