Long range and highpower shooters ( the top ones anyway) get sub-moa accuracy out to 1000 yards with charge variations of .2 to .3 grains in the .308. They often use IMR4064 and IMR4895, and although 4064 does not throw consistent charges many prefer it because accuracy is better even with the variation. This is hard for the average handloader to accept given all the BS published in the slicks, but it is proven every year in competition. Short range BR shooters prefer less variation, but do they really need to? Virtually none of them weigh their charges.....but they shoot bughole groups anyway.
One thing these guys do is shoot a lot. They shoot enough groups - and record their results - to get a real picture of what effects accuracy. The average shooter's "testing" consists of shooting a few groups at 100 yards with one load, averaging the group size, then moving on. Statistically this method is BS and proves very little, although we usually fool ourselves into thinking our load shoots better than it does.
Shooting at 100 yards is also a poor way to test loads that will be used at longer ranges. A load which shoots 1 moa at 100 yards may not do so at 500 yards. This may be due to the load, but more likely it is due to the environment. Wind, mirage, temperature, shooter skill - all play a major role in long range accuracy. Bottom line is that at longer ranges minor differences in charge weight is completely overshadowed by outside factors.
Last edited by Lone Star; 12-04-2005 at 07:42 AM.
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