The range of evidence in firearms-related cases can be as small as a piece of a bullet fragment which has rifling marks or as large as hundreds of bullets and cartridge cases and numerous firearms. Even from small samples, information can be developed to indicate the type of firearm used and possibly identify the actual firearm that was used.
Other firearms evidence that could be found at a shooting scene includes shotshell wads and shot pellets; these can indicate the gauge of the shotgun. Wads and pellets can be gathered and preserved in the same manner as bullets and cartridge cases.
By examining wadding materials, the examiner may be able to determine
The gauge of the shotgun
The manufacturer or marketer
A range of possible shot sizes based on impressions in the shotshell wad
