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Old 09-02-2014, 10:37 PM
sigman2 sigman2 is offline
Join Date: Oct 2009
Location: North Alabama
Posts: 6,076

45.0 grs. is a considerable load reduction given the original charge weights.

Even though this ammo is HXP 1978 they could be from different lots. The powder burning rate will vary from lot to lot so the charge weights will vary accordingly. There will always be very minor variations in the powder charge of ammo from the same lot. The powder charges are measured by volume, not individually weighed. The 53.6 to 58.4 gr. charge shows that these are from different lots.

If you take ten rounds from ten different lots and adjust the powder charge to the same weight you will have a real mixed bag of loads. Remember there were usually multiple lots run in the same year. Head stamp year does not mean the ammo is the same as far as charge weights. You need to separate your ammo by lot numbers which is not possible with loose ammo. This is why I prefer not to buy loose ammo.
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In honor of my father, Howard C. Ricks. Corporal, Co. E, 2nd Battalion, 20th Marine Engineers, 4th Marine Division. Later renamed Co. B, 4th Pioneer Battalion after Marianna Operation. Service dates February 1943 to October 31, 1945, Combat action: Roi-Namur, Saipan, Tinian and Iwo Jima. His rifle SA 893999 met "Captain Crunch".
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