Inexpensive subsonic ammo? Yes!
Palmetto Projectiles are makers of a nice little 203 gr. polymer-coated hard-cast lead projectile. The polymer coating does not come off, so your barrel is left squeaky clean (well except for all that poorly-burned powder - welcome to subsonic). You have to try it to believe it! We load this to a conservative 1,070 FPS (the speed of sound at sea-level is around 1,150 FPS), and deliver 561 ft. lbs. of muzzle energy.
Palmetto says: "These are polymer coated lead bullets with a Brinell hardness of 18. Our 300 Blackout projectiles are specifically designed for subsonic application on both AR platforms and bolt action rifles. They work well in both metal and polymer AR magazines and feed well with AR15 and M4 feed ramps."
Sold in a 20-pack. This is lead ammunition and uses reformed mil-spec Lake City brass.
Please note, without a suppressor this will not reliably cycle your AR-15 platform rifle.