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labgrade · March 10, 2001, 10:51 PM

To confuse (& clear up) a little more ....

Actually, .308 INCHES = 7.823
&
7.62 MM = .300 inches .... (do the math

)

Difference in the exact same designation (IIRC) is that the US system measures groove depth, while the metric measures to the lands (groove is the final cut maximum diameter of the bbl while the lands are the starting/minor diameter). Obviously, the groove depth will be a larger reading. So, all things being equal, you'll have a .004" groove depth (1/2 of the diameter difference).

This only deals with the bullet itself and has absolutely nothing to do with the configuration of the case itself - whole 'nother deal.

March 10, 2001, 10:51 PM	#11
labgrade Member In Memoriam Join Date: November 29, 1999 Location: west of a small town, CO Posts: 4,346	To confuse (& clear up) a little more .... Actually, .308 INCHES = 7.823 & 7.62 MM = .300 inches .... (do the math ) Difference in the exact same designation (IIRC) is that the US system measures groove depth, while the metric measures to the lands (groove is the final cut maximum diameter of the bbl while the lands are the starting/minor diameter). Obviously, the groove depth will be a larger reading. So, all things being equal, you'll have a .004" groove depth (1/2 of the diameter difference). This only deals with the bullet itself and has absolutely nothing to do with the configuration of the case itself - whole 'nother deal.