WEIL SIE HÖHERE DRÜCKE PRODUZIERT.
Ich sage Bullshit.

Die .308 ist geringfügig schwächer.
One of the most noted misconceptions between the 7.62mm NATO and commercial .308 Winchester ammunition; "the .308 Winchester generates significantly higher pressures than 7.62mm NATO ammunition". This is due to incorrectly substituting the SAAMI (piezoelectric transducer) pressure measurement system with the (Copper Units of Pressure, "CUP") measurement system. The original specifications for 7.62mm NATO (M80 BALL) ammunition uses the CUP (Copper Units of Pressure) method. The commercial ammunition usually conforms to the SAAMI standards using the (piezoelectric transducer system) AND/OR the (Copper Units of Pressure, CUP) pressure measurement systems.
For example, 7.62mm NATO ammunition that has been subjected to 125°F to -65°F storage conditions can have an average pressure that shall not exceed 55,000 CUP (Copper Units of Pressure).[1] Whereas commercial .308 Winchester ammunition can have a SAAMI/ANSI maximum average pressure of 62,000 PSI (piezoelectric method) OR a maximum average pressure of 52,000 CUP (copper units of pressure);[2] both of these measurements from SAAMI are one and the same, they just represent different methods of measuring (such as inches and millimeters).
Das wahre Problem liegt in den dünneren .308 Hülsen und dem anderen Headspacing der 7,62 NATO.