It's not the barrel or slide, it's the barrel.
Just the barrel assy. It is an assembly, but one that once made, does not come apart. And that's why it can't be cleaned the way other gas systems can be. You would literally have to cut it apart to get access, and then you'd have to weld it back together AND get it in spec, Cheaper and easiter to just replace it.
There are four (4) right angle turns in the gas path, its not something you can really clean.
I know of a guy who did not follow DE's recomendations. He shot lead bullets in his. It did plug. NO idea how many rounds were fired, but not a lot, couple boxes or so, I think. He took it to our local smith. (A real old time smith with decades of skill and experience) He couldn't clear it.
Gun wound up going back to Desert Eagle. When the gun came back, it had a new barrel, and a bill for the new barrel as well. (nearly half the cost of the gun!)
Replacing a plugged barrel because YOU ignored the rules and shot lead bullets is NOT covered warranty repair work.
Can't tell you how many rounds it will take to wear out a DE, but I can tell you that you can BREAK ONE with a small number of the wrong kind of rounds. Jacketed bullets only, and only jacketed bullets with no exposed lead at the base. And loads need to be pretty much "full house" or the gun won't cycle. Its NOT ADJUSTABLE!!
