Why does our load data differ from other sources?

We sometimes get asked why our loads differ from other sources. Often, it is then the case that different components are compared. Please make sure you compare apples with apples. If loads still deviate, it can mostly be attributed to the following reasons:

Safety Buffer

Our load data (maximum load) contains at least a 10% safety buffer in regards to the maximum allowed pressure for a specific caliber. Hence, our listed maximum loads might be lower than loads proposed by powder or bullet manufacturers who do not include such a safety buffer.

Cartridge Dimensions

The charge (weight of the load) is the key driver for the maximum pressure achieved by a reloaded cartridge. However, there are more factors, specifically those that influence the free combustion chamber volume. The general rule is: The lower the free combustion chamber volume, the higher the achieved pressure for an identical load, hence cases with a lower volume generate higher pressure.

Hence, cartridges with a lower overall length (OAL) in the same caliber and with the same bullet also create higher pressure because the bullet seating depth is higher and the free combustion chamber volume is lower.

We provide for each load the underlying cartridge specifications: Bullet Length, Case Length, Cartridge Length / OAL, Seated Depth, and Case Capacity. Reloaders might deviate at their own risk from our load data if their cartridge specifications deviate:

• Bullet Length: With all other specifications being equal, greater bullet length allows for less powder

• Case Length (l3): With all other specifications being equal, greater case length allows for more powder

• Cartridge Length / OAL: With all other specifications being equal, greater OAL allows for more powder

• Seated Depth: With all other specifications being equal, greater seated depth allows for less powder

• Case Capacity: With all other specifications being equal, greater case capacity allows for more powder

Suboptimal / Incorrect Manufacturer Data

The load data of the powder and bullet manufacturers sometimes simply contains errors or is based on suboptimal inputs (i.e., too little powder leading to a too low fill rate, too much powder, or physically not fitting into the case mentioned). 

Errors in our Data

We can not exclude the possibility of making mistakes. For example, we sometimes get incorrect bullet measures from manufacturers. With that, our load data can be incorrect because the calculated seating depth and free case volume are incorrect.

Please contact us if you believe our load data is incorrect, and let us know which source you are exactly comparing with which of our data.