The US Army is testing two weapons that they think will alter firearms tech. One is the Lockheed/Teledyne EXACTO rifle in .50 BMG which uses optical sensors to guide the round to target. How the bullet steers is classified, but may use a pinhead camera and air channels. The other is a laser riding flechette with wings made by Sandia Labs. The bullet rides a laser. I find it amusing that the Germans who are making secret weapons again, reject these guns. They have a plasma rifle in development, gas jet cannon, have invented laser flak stationary and for mobile armor, and the Leopard 3 tank with the 140mm Rheinmetall gun can fire at Mach 6 not needing a rail gun that fires Mach 7 for 5 rounds and then overheats! Oh, and the Germans just invented a laser freeze ray and dominate Quantum computer tech and supersoldier tech for the Bundeswehr.

Note: tech is not that new. Nazis had rocket bullets in WW2 with experimental guns and used rocket assisted artillery shells operationally.