I recently built a new 30 Nosler, opting for a 22-inch barrel instead of the longer 26-28 inch barrels used in my previous builds. This rifle is equipped with a TBAC Magnus suppressor. While researching potential loads and powders, I initially assumed that a faster-burning powder would be more suitable given the shorter barrel length, as it would facilitate a complete powder burn and yield better velocity and standard deviation (SD) values. My bullet of choice was the Berger 215-grain, and I began my testing with H1000 powder. This initial load demonstrated decent accuracy and SD, with a velocity of 2,890 fps at 82 grains.
Next, I tested Retumbo, which provided significantly higher velocity, reaching 3,104 fps at the first signs of pressure, along with slightly improved SD values compared to H1000. I then tried 4831sc, which produced a velocity similar to H1000 but resulted in worse SD values. Finally, I opted for N570, the same powder I use in my other 30 Nosler rifles, and found an optimal load at 86.2 grains, achieving a velocity of 3,007 fps with an SD of 1.2 (2.8 fps extreme spread).
Contrary to my initial expectations, the shorter barrel performed better with slower-burning powders. Based on this experience, I conclude that for heavy bullets in any given caliber, slower powders yield better performance regardless of barrel length. Anyone else have similar or differing experiences?
Next, I tested Retumbo, which provided significantly higher velocity, reaching 3,104 fps at the first signs of pressure, along with slightly improved SD values compared to H1000. I then tried 4831sc, which produced a velocity similar to H1000 but resulted in worse SD values. Finally, I opted for N570, the same powder I use in my other 30 Nosler rifles, and found an optimal load at 86.2 grains, achieving a velocity of 3,007 fps with an SD of 1.2 (2.8 fps extreme spread).
Contrary to my initial expectations, the shorter barrel performed better with slower-burning powders. Based on this experience, I conclude that for heavy bullets in any given caliber, slower powders yield better performance regardless of barrel length. Anyone else have similar or differing experiences?