Hi el1234,
Waiting for the true Jedi Masters here to offer their insight, but here are my thoughts.
FCD is pretty much worthless for 9mm in general, as the stickies etc here will attest. There's a lot on that here, and it causes more issues than it solves. All you need for 9 is to remove the flare/bell, and a micrometer and small incremental turns of your crimp die (not FCD) will get you there in 5 minutes.
And nothing really addresses the low bulge in 9mm brass like you might see in hot loads in a less-than-fully-supported chamber. 9 is a tapered case so you can't full length bulge-bust easily like you can with 40 or 10 etc etc.
If you are using range brass, maybe you are picking up brass shot in open guns. Do not use. Indoor range brass is usually NOT from open guns. It's usually factory ammo often bought at the range. But still, you never know. Mixed brass from unknown sources is our scourge.
To your point, a mildly sticky case now and again that still fully chambers (with light pressure) and can be easily plucked out is common, especially with the crap brass floating around. Aquila is notorious. I don't like several other headstamps, but point is, those will shoot fine. I shoot those. but I remove them from my shock bottle and toss into the "shoot and toss the brass" bucket just because I have enough quality brass to not bother keeping them. But the rounds that will not chamber with slight fingertip pressure (like someone roll-tapping their fingers on a desktop distractedly) those should be pulled apart to recover your components and toss the brass into the trash. For me, many of these once tapped in, subsequently chamber effortlessly afterwards. I concluded the issue was a slight lick-curl of brass from resizing or case-mouth expansion die, or something and the tap essentially removed it.
Many high volume shooters (I've loaded about 275k 9mm at this point, and now I use an automated press) use the 100 round "shock bottle" products as our chamber check process. I use the version made by Armanov which comes with a tapered tray that sits atop it to help speed the insertion process. These case gauge trays are CNC'd. They are generally tighter than the average chamber, and it's even tighter than my CZ barrel - which I test regularly. So if it drops in there easily, and will lift up partially and fall back down fully when you jerk the tray up quickly, it's the equivalent of the 'plonk' test in my CZ barrel. These fall out when the tray is inverted into ammo trays.
Rounds that will not seat/chamber with very light pressure are not to be used; generally, these are the jams when shooting.
Best,
C