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Firearms Examiner Training

Physical Features

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Physical Features

FMJ and lead round nose bullets
FMJ and lead round nose bullets
Courtesy of Ronnie Freels (see reuse policy).

Most modern bullets fall into two categories:

Within these two categories, there are a wide variety of bullet designs intended to improve performance for a particular purpose.





Courtesy of Ronnie Freels (see reuse policy).

Common Terms



Bullet Nonspherical projectile for use in a rifled gun barrel
Tip Extreme forward end of a bullet
Meplat Blunt tip of some bullets, specifically the diameter of that blunt tip
Ogive Curved forward part of a bullet
Nose Forward end of a bullet, including the tip, the ogive, and meplat (if present)
Cannelure Circumferential groove in a bullet generally of a knurled or plain appearance for the purpose of lubrication or identification, or to assist in crimping a bullet in the mouth of a cartridge case
Bearing surface Portion of the outer surface of a bullet that makes direct contact with the interior surface of a gun barrel
Base Rear portion of a bullet
Heel Configuration of the intersection of the bearing surface and base of a bullet



The categories of physical features of bullets are extensive and can be used to search reference materials for bullets with similar features.

The primary physical features of bullets include these:

  • Weight
  • Measured caliber/diameter
  • Composition
  • Jacket type
  • Magnetic properties
  • Length
  • Color/finish
  • Base construction
  • Base shape
  • Nose construction
  • Nose shape
  • Cannelures


The weight of a bullet is normally measured in grains using a balance. There are 7000 grains per pound or 437.5 grains per ounce.

The weight of a relatively intact bullet is a partial indicator of the type(s) of cartridge that may have contained the bullet. Weight is one of the factors used to determine cartridge type(s).

Weight in grains of bullet
Weight in grains of bullet
Courtesy of Ronnie Freels (see reuse policy).
Weight in grains of bullet fragments
Weight in grains of bullet fragments
Courtesy of Ronnie Freels (see reuse policy).

In the following chart, the weight of a bullet in grains corresponds to possible cartridge type(s). A bullet weight may overlap several cartridge types, indicating that more data are needed to narrow the field.

Range of Bullet Weights for
Various Cartridge Types
17 Remington 25
22 Short 27-30
22 Long Rifle 36-40
22 Win Mag 30-50
25 ACP 45-50
7.62 Tokarev 84-92
7.65 (30 Luger) 90-96
32 S&W 85-88
32-20 WCF 90-115
32 Short Colt 80
32 Long Colt 82
32 S&W & 32 S&W Long 95-100
32 Auto 60-71
8mm Nambu 99-103
380 Auto 85-102
9mm Parabellum 88-147
9mm Makarov 90
9mm Steyr 114-118
9mm Mauser 123-128
38 S&W 145-150
38 Long Colt/Colt New Police 148-150
38 Special 95-158
357 Magnum 110-180
38 Auto 115-147
40 S&W 141-180
10mm Auto 155-200
41 Rem Magnum 170-240
41 Short Colt 160-167
44 Rem Magnum 180-275
44 S&W Spl 200-246
45 ACP 175-230
45 Colt 225-255
Popular small caliber excluding reloads
Sources: Hatcher, H.P.White Lab, CCI, Winchester, Remington, Federal



When obtaining the remaining weight of a fired evidence bullet, the examiner should bear in mind the following considerations:

Ultrasonic cleaner
Ultrasonic cleaner
Courtesy of Ronnie Freels (see reuse policy).
  • Laboratory safety protocols should be followed.
  • Laboratory trace evidence policies should be followed prior to and during removal of any material adhering to a bullet.
  • Bullets should be cleaned so as to not damage the surfaces potentially bearing microscopic marks.
    • Soak in a mild detergent to loosen any adhering material. Gently scrub using a soft bristled toothbrush.

      • Use an ultrasonic cleaner and appropriate fluid.
        • Follow the manufacturers recommendations.
        • Treat one bullet/fragment at a time.
        • Monitor and observe bullets during treatment; ultrasonic cleaning may alter the microscopic details on the surface of a bullet.
      • Use appropriate tools to mechanically remove debris (e.g., embedded wood particles, bone, cartilage).
  • Weigh each bullet fragment separately because they may or may not originate from a single bullet. Individually weighed fragments can be regrouped later, if necessary.

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