How about with a rifle?

Again, you are in a lull in the fight and want to load a fully loaded magazine into the weapon.

Holding the loaded mag in your hand, release the partially loaded mag and save it.

Give the new mag a firm bump with the palm of your hand to fully seat it.

You can then place the partially loaded mag in your pocket.

You are then faced with determining if there is a loaded round in the chamber.

You must do a Systems Check.

Pull the charging handle back with your right hand and use the finger of the left hand to feel for the loaded round on the bolt.

Release the charging handle and let the bolt go forward.

Use your finger on your left hand to place it in the groove in the bolt and pull the bolt fully closed.

Do not use the Forward Bolt Assist.

Why?

As Clint says, "If that round doesn't want to go into the chamber easily, why in the world would you want to force it into the chamber. Eject it and load another round."

You are now ready to return to the fight.

You have a fully loaded rifle and are assured that the chamber is loaded.