.30-06 Springfield wildcat cartridges

.30-06 Springfield wildcat cartridges are cartridges developed from a 30-06 Springfield "parent cartridge" through narrowing or widening the cartridge neck to fit a smaller or larger bullet, or modifying the overall shape of the case, in an attempt to improve performance in specific areas. Such wildcat cartridges are not standardized with recognized small arms standardization bodies such as SAAMI or CIP. == Parent cartridge == The 30-06 Springfield cartridge (pronounced "thirty-ought-six", "thirty-oh-six") or 7.62×63mm in metric notation, was introduced to the United States Army in 1906 (hence "06") where it was in use until the late 1970s.

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