My 6.5x284 has a 1:7.5 twist, so stabilization wasnt a problem. It also shot well for me with Ramshot Magnum at 2750 fps. I know not a 6.5x55- just info about accuracy in my rifle.

Last year, large whitetail doe at about 50 yards, quartering away shot.
Exit hole
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Chest cavity, notice hole in heart and off side lung soup (poured out)
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Exit hole
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So far (sample of 1), I have been pleased. Hopefully I will have another whitetail volunteer this coming weekend.