Meant to post about this last night, but forgot. I was reminded this morning by footage on the news of a Russian separatist firing in the Donetsk region.
Anti-tank rifles, like the the PTRS-41, would make a comeback in the Twilight War. Today, they're often employed as long-range sniper rifles, but more often as anti-materiel weapons.
https://en.wikipedia.org/wiki/PTRS-41
Obviously, anti-tank rifles are fairly useless against modern AFVs, but they can still do significant damage to soft-skin and light armored vehicles. For example...
In the T2k PbP I play in, two different OPFOR have used anti-tank rifles against the PC's BTR-80 in the last two major firefights, managing to poke a few holes in it, damage the engine, and wound a couple of people.
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