Under 400 yds, the difference is pretty much negligible. I've shot 2 elk and 2 deer with my 300 WSM so far (all 300 or less) and I could have done it just as well with a 30-06. Just guessing, I'd say the 300 velocity at 400 yds is about the same as the '06 at maybe 300. Either is more than adequate for the job.

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