Flatlander is absolutely correct, so far as I've seen.
Having worked the pits at a highpowered rifle match at 600 yards, I could really see the difference between the guys with their 26" .223's and the guys with their .308's and '06's. At 300 yards, it would have been a wash for accuracy. At 600, that 5 mph wind gusting to 8 mph sent the .22's all over the paper, and indeed, off the paper. This was about 10 years ago, though, and I believe they were using .55 g. bullets.
Regards,
L.P.
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Will you, too, be one who stands in the gap?
Matt