模块化已经成为现代轻武器的一大特点,通过更换不同的功能组件可快速改变武器的战术性能和作战用途。SG551/553系步枪采用枪机回转式闭锁方式和冷锻枪管,气体调节器有两个位置可调。该系列步枪可通过更换不同长度的枪管组件、护手组件、上机匣组件、枪托组件、握把组件及不同容弹量的弹匣,组合成多种型号的武器。 Modularity has become a major feature of modern light weapons, by changing the different functional components can quickly change the tactical performance of weapons and combat purposes. The SG551 / 553 rifle uses a bolt-on latching method and a cold-forged barrel. The gas regulator has two adjustable positions. This series of rifles can be combined into different types of weapons by changing different lengths of barrel components, hand guard components, upper case components, butt components, grip components and magazines with different capacities.