Your load data for the 7mm PRC specifically the Barnes 171gr Match Burner has substantially changed since 5/24/24 to what I see currently posted. All the load ranges look nearly the same but posted velocities look to be down graded by roughly 75-100 fps for all the loads. What changed and why?
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We have over 4m loads. They are simulated/calculated with very sophisticated powder models.
The results try to be close to reality but do deviate as they are only approximations and also because the inputs change lot by lot.
To improve our models, we collect real life pressure and velocity data to calibrate our overall models or individual caliber, powder, bullets specifics.
With the last update (see blog sectio. On homepage) we updated also our overall models to better account for powder and powder gas being accelerated together with the bullet, typically taking down velocities for calibers with a lot of powder and lighter bullets. Hope this helps.
Let us know if you have any measured velocities and how they compare to our data.