Love my Hakim too! I have to run it with the gas port almost completely closed (1 click open) or it cycles harder than necessary. Unless they are dirty or something, you probably never need to turn it up any higher than that. I've got new recoil springs in mine as well and there's no ammo (50s yugo, 90s yugo sniper, 80s romanian steel case, modern reloads) it doesn't work just fine with at 1 click open. It does seem to like the lighter ammo better than the heavy stuff but works fine with either.
Loads of fun, I shot mine a lot and at one point the front sight blade literally just fell out of its slot! lol a little threadlock took care of that though.
As for using corrosive ammo, my method is to bring some WD40 with me and after I'm finished shooting it (while still at the range) I lock back the bolt and stick the spray tube from the WD40 in the gas tube at the breech and flood the tube with it while holding the muzzle pointing down until it starts to run out the barrel. I leave it on the rack or whatever with the muzzle down to continue draining while it cools. Then I just clean the bolt and bore normally with Mpro7 when I get home. Since the gas tube is stainless, the WD40 treatment seems to be plenty for that part.