My son shoots a G34 with 147 gn. RN Blue bullets over 3.0 gn. TiteGroup at 1.14 COL. Chrono'd at Virginia State Championship at 132 PF. My chronograph says they average 903 fps. Nice and soft, but has never failed to knock down steel, and with only one failure to feed since using it, and that was on a reload. I told him it was operator error, not the ammo. It is still a point of contention between us.
You have to be careful with lead bullets in Glock barrels. The twist is something like 1 in 9.8, and if run the speed up on lead, you can throw the bullet apart. We had that problem initially with 125 gn blues, and went to an after market barrel with 1 in 32 or something. Then went to 147s. WE have shot them through the glock barrel since then without any problems.
Of course the issue for us was making minimum power factor (125) with lighter bullets (requiring greater muzzle velocity). I target minimum PF + 5 so as not to fail chrono due to temperature or a change in crimp or seating depth.