So you believe in the "news" just as presented? By anyone.
Well, advertised MV does matter for prying money out of the pockets of those who over think it. Advertising always puts a rosy light on the stuff being sold. Expect and allow for it, unless it's too egregious. No one sells stuff by understatement. Usually. It's nice if approaches accuracy tho. As noted, they likely changed something and not the web site. Enough feedback and they probably will.
Plus, are you using the same barrel, throat, twist (not, from your post), etc. they are, under the same conditions?
Or you can load your own for your desired velocity in your rifle, under your conditions. Personally, I load for best (or acceptable, at least) accuracy with the components I am using, at the time I load. I don't own a chronograph, and have never used one. It would be an interesting data point, but that's about it for my use.
One of my scopes says "1 click =1/4" at 100, but in practice, 3 clicks equal an inch at 100. But it is repeatable......I can live with that.
Trust but verify/adapt for your own use?
Sometimes "good enough" is just that. Good luck with your quest.
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