The belling operation is an easy fix, just turn the powder die down ever so slightly. It just means the CBC are slightly shorter in OAL.
How many rounds have your dies sized in their lifetime? Do you use any lube or do you run them dry? I know it takes a long time to wear dies out, maybe yours are nearing the end of their lifespan. Maybe they were borderline straight from the factory. You can easily measure the case wall thickness by comparing the loaded CBC brass to the loaded rounds using other brands. I would be surprised if there was more than .001" or .002 difference..
I have a friend that shoots high power tournaments with me, he's much more active than I am. He has worn out .223 sizing dies out before. I never have.
I sort out foreign brass and use it solely for blasting ammo. I keep Federal and Speer as my Tier 1 brass when loading handguns. Winchester and Remington is Tier 2. Everything else is for blasting ammo.
I like IMI pistol brass but will keep it in Tier 2 or blasting status because I don't get it in the quantities I consider useable. Geco, IMI, Sig, Fiochi, CBC, Seller & Bellot, Arguillo, Hornady, Extreme and any other oddball brand except A-merc (which gets trashed) get used for fun, not competition or self-defense. I simply get too few of these cases to mix them in with the large quantities of good brass I normally get. There is nothing wrong with any of these as far as I can tell, I just have the volumes that I don't need to mix them in with the brass I like the best.
Once fired brass purchased at .04 cents +/- each just isn't worth worrying about. Free range pick-ups even less so. Just chuck them if they are causing you any trouble at all.