Herter's Perfect Rifle Powder 101 was made for Herter's by Nobel in Scotland and used Methyl Centralite as the deterrent coating, which lowered the burn temperature of the powder and prolonged bore life.
I used a lot of the Herter's 101 and 102 power (especially 102) back in the seventies.
Herter's 102 had a burning rate close to IMR3031, and Herter's 101 has a burning rate close to IMR4320.
I've long since burned up all of my Herter's 102 (mostly in 5.56x45mm), but I still have a couple of cases of Herter's 101 squirreled away.
Herter's published a pamphlet of loading data for 100, 101, 102 and 103 rifle powders, and the following data are from this pamphlet copyrighted 1966:
For .308 Winchester (no data were provided on components or barrel length):
No data provided for 165gr bullets...
For 150 grain bullets:
Maximum Grain: 46.0
Velocity: 2800fps
Moderate Grain: 43.5
Velocity: 2680fps
Suggested Grain: 41.0
Velocity: 2550fps
Herter's 101 is a great powder. Have fun shooting yours up...
Forrest
WARNING: Loading data provided for informational purposes only.
As with all handloading, start low and work up...
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