Not sure what you mean by jamming up.
a photo would help.
Is the cartridge not fully chambering? Is the cartridge chambering but slide isn't going full forward?
Most firearm feeding issues are caused by the magazine.
Swap the mag out for a Factory Glock standard 17 round magazine.
Load some 115grain or 124grain FMJ round nose premium ammo and see if it chambers.
Have you disassembled and thoroughly cleaned the barrel's chamber?
Run a swab inside the chamber and verify it is smooth.
As others said, they work great out of the box, so try it with all factory parts including the slide.
Glocks are very simple spring operated machines, easy to fully disassemble and work on.
Almost anybody making a living as a gunsmith can probably fix it on the spot.