Mike, I've shot some lead bullets in my .40 (G23), Marshall's 200gr. WFNGC, and they work great. Only trouble I've had - I ran out. But some more are on the way!!
Also worked up some of the 160 gr. FNBB bullets, sized 0.358", for a G19 or G17, don't remember, and a Sig P226. Can't recall how they shot in the Glock but like a house afire in the Sig. See the tech note on "heavy 9mm bullets" that I wrote. You can get them up to about 900 fps.
There is an awful lot of BS flying around about lead bullets in Glocks. To date I have not had one bit of trouble, and a friend loads cast bullets for his many glocks without a hitch, including some pretty hot bowling-pin loads for a 10mm.
Glock of course will discourage the practice, as they tell you not to shoot reloads of any kind. Maybe that's where all the 'stuff' started.
Read the tech note and let me know if you have any questions.