I have chronographed considerable quantities of M882 fired from a Colt GM (5" barrel), and also an EAA Witness with a 4.5" barrel. MVs run in the mid-1100s. NATO specification for velocity is 1230+/-49 fps average @ 52.5’ from muzzle (from a NATO 7.848" test barrel).
The official chamber pressure specification for the 124 grain M882 is 34,519 psi (NATO method) max. average (from a NATO 7.848" test barrel). As loaded, the actual lot chamber pressure average is in the 32,800 psi range (NATO method). This information comes directly from Winchester. The NATO method is essentially the same as the European CIP, pressure is measured by piezo gauge at the case mouth. Not the same as the SAAMI method using a conformal gauge.
Last edited by DWalt; 07-26-2016 at 01:13 AM.
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