Sten - I've got a friend who put over 15,000rds through his sten with no cleaning and nothing more than an occasional squirt of CLP.
Browning 1919 - I had not one, not two, but THREE K-Bs in one of mine in the span of less than 5 minutes while using some old 8mm (late 1940's/early 50's Turkish IIRC). After the first two KBs, we just hammered the topcover back into shape with a rubber mallet, checked timing and headspace, looked for other damage (none) and went back to shooting. On KB #3, the topcover was damaged too badly to continue. The rest of the gun, however, was fine - not a scratch. After I got home, I swapped the broken topcover for an old Israeli one, vowed never to use that ammo in a machinegun again, and it ran just fine after that. I can't think of too many firearms that can withstand three near consecutive K-B's with such minimal damage to the firearm itself and none to the shooter.