The AK-257 is a Soviet 57mm naval gun, originally a land ZIF-31 L/70 57mm (Type 66/76) cannon. During the early 1950s, development began of naval versions of the 57x348mmSR 70 calibre weapon which had entered service with the Soviet army in 1950 as the S-60.

The second USS Altair (AK-257) was a United States Navy Greenville Victory-class cargo ship in commission from 1952 to 1953. She was converted into a Antares-class general stores issue ship (AKS-32) in 1953 and was in commission as such from 1953 to 1969, seeing extensive service during the Cold War.

57mm AK-725 Improved naval gun mount developed to replace the ZIF-31 and others. This enclosed gun mount has better sustained firepower, requires no crew on mount and improved radar guided fire control.

2019年6月8日 · 动力系统采用 3台柴油机，总功率22371千瓦，三轴推进，最大速度32节（59公里）。“契卡”级配备2座三单元枚ss-n-9“孔雀石”超音速反舰导弹（出口型4枚 ss-n-2反舰导弹），1 座sa-n-4近程防空导弹，1座 ak-630近防炮，一门双57毫米ak-257舰炮或1 门76毫米ak-176舰炮。

Soviet 57mm naval AA gun.

2019年1月20日 · 5艘满载排水量275吨的205P型鱼雷巡逻艇，搭载4具400毫米反潜鱼雷和2座AK-230速射炮，舷号1131至1135。 1艘172吨的206型鱼雷艇，配备2座AK-230火炮、1套9K32（SA-N-5）防空导弹、4具533毫米鱼雷发射管，舷号1115。 206M型鱼雷艇. 1134号205P型鱼雷巡逻舰. 除此之外，有15艘中国产的快速巡逻艇，舷号1141-1145和1101-1109，配备76F双管37舰炮。 1艘中国产中型登陆艇，舷号1401。 其余的基本上为小艇。 中国造巡逻艇. 柬埔寨海军的中国造 …

USS Altair (AK-257 / AKS-32) Dictionary of American Naval Fighting Ships (DANFS)

2022年6月14日 · akm是ak的改进型号，其在一定程度上改善了ak缺点，是一个改动加较大的型号。比如akm的击锤上多了一个减速器，防止了因击锤过早撞击击针导致的哑火及降低射速。再比如为了抑制枪口跳动及提高连发射击时的散布精度，akm的枪口上加装一个斜切口形枪口装置。

The AK 257 is a 57mm naval gun, originally a land ZIF 31 L/70 57 mm (Type 66/76) cannon.During the early 1950s, development began of naval versions of the 57 mm 70 calibre weapon which had entered service with the Soviet army in 1950 as the S 60

2018年10月30日 · Beyond this is a single SA-N-4 surface-to-air missile (SAM) launcher with some twenty reloads provided. Conventional armament includes 1 x 57mm AK-257 twin-gunned turreted deck gun (Series I). This was replaced by a single-gunned 76mm fit in the Series III ships.