Nosler velocities are rather consistently....ah....optimistic.
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Nosler data is shot with high quality, minimum spec barrels. What I've found is that when I use the data on my custom barrels with snug chambers it comes out real close to the real world velocity. As often as not I'll end up a grain less than their maximum charge to match their given speeds, and in some instances I've barely gotten off the starting load to match their top velocity.
When you take random factory rifles the results are mixed. Some will make speed, and some won't get within a mile of the book with their loads. Some won't make it with any load.
Mileage may vary.
