The G36 has by far the most reported stoppages of all the Glocks. I hope yours ends up working better for you, especially with defensive ammo. It's possible that the FMJ ammo you used wasn't powerful enough to overcome the power of the recoil spring, resulting in the stovepipes.
"If the sole purpose of handguns is to kill people, then mine are all defective." - Uncle Ted Nugent