Until 1938, all M91 rifles and carbines were chambered for the rimless 6.5×52mm Modello 1895 cartridge, using a round-nose metal case bullet of 160 grains weight at approximately 2,000-2,400 ft/s muzzle velocity, depending upon barrel length. At least one small arms authority noted inconsistencies in powder types in arsenal-loaded 6.5×52mm military ammunition, often with different powder types and ammunition lots intermixed within a single clip of ammunition. The practice of intermixing powder types and ammunition lots in clipped rifle ammunition was generally avoided by arsenals of other nations, as it frequently resulted in varying bullet velocities and excessive bullet dispersion on the target.