Load Data Finder

Why published load data matters

Load data is the result of pressure testing that a manufacturer performs with specific components in specific test equipment. It tells you the starting and maximum charge for a particular powder, bullet, case and primer in a particular cartridge, and it is the only safe basis for a handload. Changing the bullet, the primer, the case brand, the seating depth or the powder can change the pressure, so data for one combination does not apply to another.

Where to find reliable data

This page links to the load-data centers that powder and bullet makers publish themselves. These are the current, official sources, and they list the test conditions beside each load. A printed manual from a bullet or powder maker is another reliable source. Be careful with load data posted on forums, videos or social media, because it may be copied wrongly, out of date or tested in another firearm.

Using load data safely

• Match every component to the listing, and check the case length and overall length.
• Start at the published starting charge, not the maximum, and work up in small steps.
• Watch for pressure signs, such as flattened or cratered primers, ejector marks and hard bolt lift, and stop if you see them.
• Never exceed the published maximum, and use an accurate, checked scale.
• Keep a written record of each load, label the ammunition and store powder and primers as the maker directs.

The calculators in the Reloading section help with planning, such as case capacity, load density and seating depth, but they are not load data. Read our disclaimer and safety notes.