I finally ran down to the local gun shop and got a mechanical loader and put this to good use. But I eventually learned a really good technique that I’ll show you here. This method works better than the traditional method. Why?
The old-school method that everyone uses only utilizes the thumb to push down on the magazine spring. This newer method, with the magazine turned around, actually incorporates the wrist and forearm muscles; therefore you have stabilizers that control the magazine while you use your thumb to press the ammo down and in.
Use your strong hand and begin to insert a cartridge into the magazine while simultaneously pushing down on the spring with the thumb of your weak hand.
Insert the cartridge fully into the magazine until it seats properly. Once you are done, continue to add more cartridges.
It may seem odd at first doing this but I guarantee it will save you time, and “wear and tear” on your thumbs. Being able to use your wrist and forearm muscles to hold the magazine gives you greater control of it and therefore the ability to seat the cartridges more quickly. Try this a half dozen times until you get the hang of it.