When you have the gun gassed up, hold the trigger against the safety. The sear should be fully forward. This where the credit card gap comes into play. With the sear fully forward, the back of the trigger should be a credit card thickness ahead of the front of the trigger rod on the sear. This will allow the sear to fully rotate forward and open the on-off to recharge the valve. Now, when you release the safety and pull the trigger, the trigger should be able to contact the trigger rod and push it far enough back to fully release the bolt. If this happens, then that part of the gun is working properly. It doesn't really matter what the length of the rod is if you follow that spec. The actual trigger rod spec won't be accurate for all setups depending on what triggers are used and what grip frames are used, but most setups will work if you follow the idea of allowing the trigger to have a gap when pulled against the safety and able to push far enough to clear the bolt.
Except for the Automag in front, its usually the man behind the equipment that counts.