<P> While the Gun Control Act prohibits the direct mail - ordering of firearms, a person may ship a gun via contract carrier (such as United Parcel Service - UPS, United States Postal Service or FedEx) to a gunsmith (who has an FFL) or the gunmaker's factory for repairs or modification . After the repair work is done, the gunsmith or the factory can ship the gun directly back to the customer . </P> <P> The GCA created what is known as the "sporting purposes" standard for imported firearms, saying that they must "be generally recognized as particularly suitable for or readily adaptable to sporting purposes ." GCA sporting purposes includes hunting and organized competitive target shooting, but does not include "plinking" or "practical shooting" (which the ATF says is closer to police / combat - style competition and not comparable to more traditional types of sports), nor does it allow for collection for historical or design interest . </P> <P> The law also required that all newly manufactured firearms produced by licensed manufacturers in the United States and imported into the United States bear a serial number . Firearms manufactured prior to the Gun Control Act and firearms manufactured by non-FFLs remain exempt from the serial number requirement . Defacement or removal of the serial number (if present) is a felony offense . </P> <P> In a June 1966 essay, Neal Knox wrote that what was then called the Dodd Bill was opposed by outdoorsmen and conservationists Harry R. Woodward, C.R. Gutermuth of the Wildlife Management Institute, Richard H. Stroud of the Sport Fishing Institute, Howard Carter Jr. of the National Shooting Sports Foundation, E.C. Hadley of the Sporting Arms and Ammunition Manufacturers' Institute, Robert T. Dennis of the Izaak Walton League, "and countless other sportsmen, and sportsmen and industry groups" because it would have a far - reaching and damaging effect on the hunting and shooting sports, while failing to reduce crime . </P>

When were guns required to have serial numbers
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