Fun fact: the Big Army still has 90mm recoilless rifles from the 1960s in active use. The Rangers use them in A’stan because they needed something with more range and punch than an M203 grenade launcher when restrictive RoE say they can’t have artillery or air support. That big fat ol’ 90mm HE round is 1960s technology with Comp B filling, and would have been instantly recognizable and comprehensible to an armorer in 1942, or 1917. But no one’s come up with anything better yet to replace it.
 
106mm recoilless rifles that the Big Army bought in the 1950s were given away as military aid around the world in the 70s and 80s and most are still in use, though they’re big enough and heavy enough that they generally put them on a pintle mount in a jeep or the local equivalent rather than breaking them down and hauling them around on foot. The Israelis still make 106mm recoilless ammo, too. Rumor has it they captured a shitload of Russian RPG29 105mm recoilless rifles and ammo for them in Lebanon fifteen years back, and they copied the Russian tandem shaped charge ammo for the 106, though if they have, they don’t catalog that one for export sales. The Israelis are still using 106mm recoilless rifles Nixon gave them.