Is this a new gun and new magazines?
I ask for several reasons...
- Magazine issues are the cause of many semi-auto functional problems. Sometimes a new spring will help revive an old magazine, but if the feed lips are bent a replacement magazine might be required. Sometimes non-factory magazines will cause feeding problems. Number your magazines to see if the problem can be isolated to only one. This will help you determine if the problem is with a magazine or the gun. Are you running extended length magazines? I've heard of some shooters running into feeding problems when using GLOCK 19 or 17 magazines. This is generally caused by the shooter's grip applying pressure on the extended magazine and changing the feed angle.
- Of my multiple GLOCKs the only malfunctions were related to the combination of tight new recoil springs, weak range ammo, and a small shooter "limp wristing" the gun. I had that same shooter grip the gun higher and it would run flawlessly with the same ammo. Otherwise, my GLOCKs have fed everything I've put through them. You mention Hornady ammo, so I don't suspect the quality. However, I would suggest some heavier rounds... 124 grains or heavier. Sometimes the tight springs on a new gun will need some break-in cycles and heavier rounds can help them run without stumbling. What brand and weight range ammo worked for you?
Clean it and take it shooting again. Remember GLOCKs don't need a lot of lubricant. Give it a good workout with several types of ammo and see if it is running any better. Try to isolate it to an individual magazine. If after a few more range trips it still is acting up, I would contact the factory.
As to my carry ammo I've had good function and accuracy with Speer 124 grain Gold Dots. However, most ammo manufacturers have a line of "premium" self-defense ammo which should serve you well.
Keep us posted.
Edmo