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Old October 14, 2011, 10:43 AM   #12
Unclenick
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Join Date: March 4, 2005
Location: Ohio
Posts: 10,247
One more note about scary Garand loads. The gun can take more than a lot of manuals would lead you to expect. If you are shooting surplus M2 ball that is old enough to have IMR 4895 instead of WC852, then you'll find it was loaded to 2800 fps as measured at 78 feet from the muzzle. The M2 bullet is 152 grains +0/-3 grains (150.5 grains average) and its ballistics cost it about 0.833 fps per foot of travel in that velocity range, so these rounds would be at 2865 fps at the muzzle, 2857 10 feet from the muzzle, and 2853 fps 15 feet from the muzzle on average.

Those velocities would be from a tight velocity barrel chamber and bore, and are likely to be lower in your gun (as will the pressure be). But my point is that it takes anywhere from about 49 to 51 grains of canister grade IMR 4895 to get that bullet to that velocity in a tight barrel using LC brass, depending on the lot number and on what primer you use, so you've got some wiggle room. The military used to use a 50 grain charge at one point, so their bulk lot of IMR 4895 at that time must have been close to what canister grade burn rates are today.

My main point is, while I would not encourage you to load hotter than necessary (no point in loading hotter than best accuracy anyway), if your gun's gas system tolerates surplus M2 ball then it tolerates the higher load levels mentioned anyway.
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Last edited by Unclenick; October 14, 2011 at 10:48 AM.
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