Originally Posted by Don P
What I'll add to the good above advise is which feels more natural while doing the reload...
What feels natural isn't always the best idea. A big part of training and practice is to overcome instinctive reaction and to learn to automatically do instead what is most appropriate.
For example, when driving a car, one's instinctive reaction in the event of a skid is to apply the brakes. We know that is the wrong thing to do; and so, if one is lucky enough to get some training in high speed driving, one learns to stay off the brake, turn into the skid and, under some circumstances, even gently apply some throttle.
Pretty much the standard is bullets forward. Why that's the standard was well described by Shawn Thompson in post 2:
Originally Posted by Shawn Thompson
...With the magazine positioned on a belt with the bullets facing forward, driving your thumb down between your torso and the magazine and gripiping it between your thumb and your traffic driving finger, your index finger will lie nicely down the front. The movement from the belt to the mag well then is a natural and indexable motion than can easily be repeated and without having to look - put your finger in the loop.
Furthermore, this positioning opens up the flat back edge of the magazine to the flat back edge of the magazine well, another solid index point. In Addition, rolling the fingers forward opening up your hand (pointing your fingers down range) while seating the magazine will stretch out the skin on your hand slightly and help prevent getting it pinched between the magazine base plate and the lip of the mag well...
When doing something in a particular way has articulable advantages, it's often a good idea to train and practice to do it that way.