The .30 Bellm is a wildcat rifle cartridge developed by Mike Bellm. It is based on the .30-30 Winchester cartridge, but necked down to .30 caliber and typically improved by providing a sharper shoulder angle and less body taper. This modification is intended to increase the case capacity and, consequently, the performance and velocity of the cartridge.
Commonly, the .30 Bellm is used in hunting contexts due to its enhanced ballistic properties compared to the traditional .30-30 Winchester. It is particularly favored for taking medium-sized game and can be chambered in single-shot and lever-action rifles. The increased velocity and maintained accuracy at longer ranges make it an attractive option for hunters looking to push the performance envelope of the .30-30 platform.
As a wildcat cartridge, commercial ammunition and standardized loading data might be limited, requiring handloading practices tailored to the firearm it will be used in. Enthusiasts typically use it for its superior ballistics and the challenge and satisfaction of working with a custom cartridge.