Powders behave differently in different rifles and cartridges which is why burn rate charts are relative things. VV labs are constantly testing, I'll take what they say about their powders. Variations in lot numbers can throw powders all over the place.VihtaVuori's burn rate chart lists VihtaVuori N150 somewhere close to IMR-4350. My first-hand experience and their published load data, shows it to be almost identical to N140. Published maximums are within .5 to .8 grains of each other with close to identical top speeds.
VV shocked me when they put out a video where the techs said the 500 series powders are more temp stable than the 100 series.









