There are many benefits and drawbacks to the various types of reloading powders.
Ball powders are the most commonly used powder due to their low cost, as well as their broad range of uses and applications. They also tend to be cheaper than the other powder types. One drawback with ball powders is that they are less efficient due to the way they fill the powder measure. Additionally, ball powders have a larger diameter, so they do not pack as efficiently as other powder types.
Flakes and sticks have to be pressed into the measure, but balls can simply be poured into the cartridge. Flake and stick powders have a smaller diameter, making them more efficient in the powder measure. They also provide a closer pack and produce less resistance when fired, which can lead to greater accuracy and lower pressures. On the downside, flake and stick powders are more expensive than ball powders.
Lastly, extruded (stick) powders are typically used for rifle ammunition because of their high energy and low flash. These powders are produced by pressing a solid rod through a die, which then breaks into short pieces (typically six to eight inches in length). These sticks are then broken up into smaller pieces for use in reloading. Although there are a few exceptions (such as IMR PB), most extruded rifle powders have the same physical and chemical properties when produced by different manufacturers.
For more information, see our article on How to Choose the Right Reloading Powder
https://tacticol.com/how-to-choose-the-right-reloading-powder/