Apart from swabbing the bore and wiping down the metal, my Remington 552 (Circa 1976?1978? reverse checkering and sickening varnish) has digested everything I've jammed down the tube. Bricks and bricks and bricks. Usually Remington, sometimes CCI.
In early 2000's, I did a full teardown, because I got my own house and tools and internets with exploded diagrams. Pulled a Frito-sized chunk of residue off the case deflector, rinsed and lubed the moving parts and put it together.
Still shoots fine. In 40 years of use, a period of that time rusting in an unheated garage, I cannot ever recall a fail to feed. A few fail to fire, but that wasn't the gun.
Not my go to weapon for anything but the gravel pit, but it's been rock solid.