Load Ramp? You mean the feed ramp on the barrel? Doubt that, the px4's practically feed directly into the barrel's feed ramp or barrel. What weight ammo are you using?Try WWB 230 grain or the Hornady you're using. Sounds like you arn't getting enough umph to cycle properly, The hornady jhp steel match I suspect is loaded hotter 930fps compared to the 830fps PMC. Remington UMC is also known to be on the weak side as well. If you are referring to PMC Bronze(RMC?) in my experience that stuff especially lacks in the powder department. I'd suggest you buy a new recoil spring from Brownells to see if thats a fix and run WWB 230grn for starters or the Hornady. If that doesn't work call Beretta.In any case your PX4 should be running everything, but I'm fairly confident it will run all the hotter stuff but not the weaker stuff w/ your current recoil spring. I don't think it's a feed ramp issue, nor a magazine issue, but a cycling issue w/ weaker ammo problem?