M77为90mm火炮历史最悠久的弹药之一，在1944年中期作为90mm M1/2/3的AP得到使用。 此弹药在实测中600码击穿黑豹首上，引起美国高度重视。 后于1944年末被自己的改进型T33替代。

The 90 mm gun M1/M2/M3 was an American heavy anti-aircraft and anti-tank gun, playing a role similar to the German 8.8cm Flak 18. It had a 3.5 in (90 mm) diameter bore, and a 50 caliber barrel, giving it a length of 15 ft (4.6 m).

2020年7月19日 · T33十分擅长打大倾角，是90mm M3最适合打大倾角的穿甲弹，原因是T33撞击装甲时，弹体碎裂，变成钝头弹。 实测中，T33分别在500码和1000码击穿了美军测试用的85/55的黑豹首上：

2022年1月31日 · 通过加膛压（膛压从M3A1的38000psi猛增至T119的47000psi）的方式，美国开发出新一代90mm火炮—T119。 T119E1被定型为M36，并被安装在M47上。 不久后，轻量化的新90—T139问世，并被定型为M41，安装在M48上。

2022年10月25日 · M77是一种钝头AP，在撞击大倾角装甲时，其弹头会碎裂成钝头AP，从而更好的侵彻装甲，相比0距离也无法击穿黑豹首上的M82，M77可以600 yd击穿，在1944年中期，已经相当不错了。

This cartridge is an obsolescent armor piercing model currently used for training purposes in 90mm guns. The projectile is a hardened steel monobloc slug and has no windshield. The projectile base is threaded to receive a tracer. The brass or steel cartridge case is loosely packed with propellant and is fitted with a percussion primer in the base.

The 90mm Armor Piercing Shot T33 is issued as a fixed complete round for the Gun, 90mm, M3 mounted in Heavy Tank, T26E3 and Gun Motor Carriages, M36 and M36B1. The shot is a modification of the standard AP, M77 which has been reheat-treated and to which a ballistic windshield has been attached.

2024年1月30日 · M77为90mm火炮历史最悠久的弹药之一，在1944年中期作为90mm M1/2/3的AP得到使用。 此弹药在实测中600码击穿黑豹首上，引起美国高度重视。 后于1944年末被自己的改进型T33替代。

*90mm M77 AP加了一条计算出来的穿深： Calculated based on Terminal velocity curve and known penetrations of 5.5in at 1000yds from TM 9-1901 and 600yds for Panther Glacis at the Isigny Tests. 60° is calculated from 2.5in at 2323ft/s ballistic limit..

This cartridge is an obsolescent armorpiercing model currently used for training purposes in 90mm guns. When the weapon is fired, the burning propellant ignites the tracer and creates gases. The gases propel the projectile out of the gun tube and ignite the tracer which burns for a minimum of three seconds of projectile flight.