the 19th-century black powder velocities of under 2,000 feet per second (610 m/s). Until the late 19th century rifles tended to be very long, some long rifles reaching approximately 2 m (6 ft) in length to maximize accuracy, making early rifles impractical for use by cavalry. However, following the advent of more powerful smokeless powder, a shorter barrel did not impair accuracy as much. As a result, cavalry saw limited, but noteworthy, usage in 20th-century conflicts. The advent of the massed, rapid firepower of the machine gun, submachine gun and rifled artillery was so quick as to outstrip the development of any way to attack a trench defended by riflemen and machine gunners. The carnage of World War I was perhaps the greatest vindication and vilification of the rifle as a military weapon. The M1 Garand was a semi-automatic rapid-fire rifle developed for modern warfare use in World War II. During and after World War II it became accepted that most infantry engagements occurred at ranges of less than 300 m; the range and power of the large full-powered rifle cartridges were "overkill", requiring weapons heavier than otherwise necessary. This led to Germany's development of the 7.92×33mm Kurz (short) round, the MKb-42, and ultimately, the assault rifle. Today, an infantryman's rifle is optimized for ranges of 300 m or less, and soldiers are trained to deliver individual rounds or bursts of fire within these distances. Typically, the application of accurate, long-range fire is the domain of the marksman and the sniper in warfare, and of enthusiastic target shooters in peacetime. The modern marksman rifle and sniper rifle are usually capable of accuracy better than 0.3 mrad at 100 yards (1 arcminute). 3D printed rifle The Grizzly is a 3D printed .22-caliber rifle created around August 2013. It was created using a Stratasys Dimension 1200es printer. It was created by a Canadian only known by the pseudonym "Matthew" who told The Verge that he was in his late 20s, and his main job was making tools for the construction industry. The original Grizzly fired a single shot before breaking. Grizzly 2.0 fired fourteen bullets before getting damaged due to the strain. In October 2020, another 3D-printed 9mm rifle known as the "FGC-9mm" was created. It is reported that it can be made in 2 weeks with $500 of tools. A second model was later made in April 2021. Youth rifle A