Is the gun factory stock, or modified (especially striker spring)?
Is the striker channel clean and DRY, or does it have oil, grease, or crud in it?
Did the cartridges fire on the second try?
OKFC makes a good observation; striker fired pistols- some have a soft strike, and will not dependably set off all ammo types.
I run 3 different 9mm, and all of them run Federal ammo with no issues.
Try to re-fire the rounds if possible, after inspecting the striker assembly.
