I load for a Glock 20 G4 with a Lone Wolf barrel that is the same length as the OEM barrel.
Hornady 180gr XTP's - New Starline Brass - CCI #300 - 13.0 grains of AA#9 = 1150-1200 fps depending on the season, and how heavy, or light handed i was throwing charges.
The OEM barrels velocity seem to...