The M1 fired only one shot and would then have to be manually reloaded. Other difficulties such as high recoil also plagued the M1. Improvements, such as the addition of a carrier/lafette backpack and a longer barrel, led to the M1A1 variant, but at 21 kilograms its combat weight was deemed excessive.
The M1 was essentially a sniper weapon, not primarily intended for military field application, but for anti-terrorist police and special forces\' use, who operate on the \"one shot, one hit\" principle. The single shot action was designed to reduce the number of moving parts and allow for extreme precision, five hits out of five shots fit in a 25 centimeter radius circle at 1300 meters.
A semi-automatic version of the M1 was later produced. Dubbing it the M2, designers reduced its barrel length and weight. An even shorter paratrooper variant dubbed M2A2 made it more favorable to Airborne and Special Operations Troops, especially because it could be fired from the hip, thanks to the advanced recoil mechanism.
M3, with a larger 14.5 mm caliber, added new destructive capability as well as increased accuracy and range, making the M3 the most popular of the Gepard rifles.
The M4 and M5 werer improvements on the M2, with stronger materials and better reliability. M5 is a bolt action rifle for military sharpshooters and weighs only 13 kilograms, while the M4 is a semi-automatic anti-materiel rifle. The massive 10-round drum magazine, so characteristic of the M2 and M3, was replaced with a straight box magazine design with a capacity for five rounds. Later M4 and M5 production fires either Russian or NATO 12.7 mm ammunition as the gun barrel is field replaceable.
The last version was the M6. This rifle used the 14.5 mm round, like the M3, but featured stronger parts and an improved scope. The M3 and M6 are strictly anti-material rifles. The accuracy of the 14.5mm round degrades rapidly at ranges beyond 1000 meters. Its high destructive power is very efficient in taking out hovering helicopters, APCs or mobile radar stations, however.