Nose construction describes the many variations encountered on all types of ammunition, for example:
- Soft point bullets provide for exposure of a portion of the core at the nose of a jacketed bullet .
- Jacketed hollow point bullets have a cavity in the nose to facilitate expansion.
- Semijacketed hollow point bullets have an exposed portion of the lead nose that contains a cavity.
- Metal point bullets ( capped bullets) consist of a standard lead bullet with a harder metal jacket over the nose to enhance bullet penetration.
- Solid nose constructed of a single metal or alloy.
Open point bullets (soft point, hollow point, and semijacketed bullets) offer opportunities to identity the manufacturer or source based on the construction of nose cavities. The details of the interface between jacket, core, and cavity are often proprietary in nature and readily observable.
|Nose Cavity Details of
Open Point Bullets
Serrations in the nose portion of the bullet jacket.
Petals of jacket material folded into the cavity to help retain the core within the jacket even after impact with a target.
Bullet nose geometry generally includes the following configurations:
- Round nose bullets are elongated with a nose measuring half that of the bullet diameter (half of the bullet diameter).
- Pointed types.
- Wadcutter bullets have a sharp shouldered nose intended to cut target paper cleanly to facilitate accurate scoring.
- Flat nosed bullets have a flattened tip at right angles to its axis.
- Semiwadcutter bullets have a distinct short truncated cone at the nose end.
- Truncated bullets are conical with a flat nose.
As previously mentioned, there are two types of circumferential grooves:
Cannelures may or may not serve a functional purpose on a given bullet. They are very useful in determining the manufacturer and, in some cases, the stock number of bullets that are used only for specific purposes.
It is useful to document the number of cannelures found on each type of bullet; this further limits the number of candidates when searching for similar examples in reference resources (primarily in a laboratory Standard Ammunition File [SAF]).
The location of each cannelure in terms of its height above the base of a bullet is another physical feature or set of physical features used as an additional filter to limit the field in searching reference files.
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