Lee dies themselves can be the problem. If crimping ever improves accuracy, there was a problem that should have been solved via some other method.
Just because Nosler data shows a higher (or jus different) charge weight than Hodgdon, doesn’t mean that their data is wrong, faulty, or intentionally misleading. Nosler uses Nosler brass(Norma), and sometimes uses barrel lengths and twists that are offered in Nosler guns. You should definitely alter your velocity expectations based on your own barrel length. You should always start 10% below max and work up watching for signs of excess pressure. Not only do different brands(and lots) or brass have different internal capacities, but different lots of powder have different burn rates and energy densities, and different barrels and chambers have their own minor variations as well.
Hodgdon manuals and their online database contain an enormous number of loads that haven’t been tested in many decades. Ever notice loads with pressure listed in CUP? That load has not been tested by Hodgdon since before SAAMI changed from CUP to PSI. Before Hodgdon bought IMR from Dupont, Hodgdon and IMR powders sharing the same number were different powders. Since that merge occurred, some IMR powders were replaced with their Hodgdon equivalents with neither a change in the label nor an update to the load data. Hodgdon has even completely changed powders without changing the name, the label or the load data. They operate on the basis that if a powder is within 5% on burn rate and energy density, then it’s basically interchangeable.
When accounting for barrel length and brass, I’ve found Nosler load data to be as reliable as anyone else’s, and they are ALL just starting points.
. I am excited and want to get this right in a safe and repeatable way.
