>I continue to use Lee FCD because aftermarket barrels have much tighter tolerances than the factory Glock.
And yet, I'll bet, unless you sign a waiver, they have to meet SAAMI drawings, so they aren't THAT tight.
Bullet manufacturer's have one major goal--to sell bullets. If the market believes that the solution to leading is harder alloy, they'll supply harder alloy. Despite over 100 years of work showing that type-metal is a poor solution, that isn't their problem.
If you ever want to actually solve your problem, you'll look into a slightly larger expander (or actually use an expander and not just flare the case mouth).
For those who always claim that THEIR gun has a "tight" chamber, why not find the cause of the problem:
Take the barrel out of the gun. Drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in barrel (or gage) and rotate it back-and-forth a few times.
Remove and inspect the round:
1) Scratches in the ink on bullet--COL is too long
2) Scratches in the ink on edge of the case mouth--insufficient crimp
3) Scratches in the ink just below the case mouth--too much crimp, you're crushing the case
4) Scratches in the ink on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit
5) Scratches in the ink on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.