I'm only lefty part time, but I run ambidextrous selectors, chargers, and mag releases on my rifles. I go back and forth about bad levers, and greatly favor the Teal Blue PDQ over the Bad levers.
When I reload lefty, I run my ambi mag release with my trigger finger, swap mags, then use the ambi charging handle to release the bolt. When NOT using an ambi charger, I just reach up and punch the bolt release with my trigger finger. I've gone back and forth over the years, practicing to use the charger or the bolt release, either works just as well.
Before I adopted Ambi mag releases, I released with my right thumb. Either way works. I generally make contact with the port side release with my right thumb any time I reach for my magazine with my right/support hand - meaning any time I'm not dropping my empty mags in the dirt, aka tactical reload or "no dent" reload. That way if I'm using a rifle without an ambi release, my right thumb goes to the right place naturally and I can use it to release the mag.
I do NOT like the video use of the right hand to manipulate the BAD lever. Really bad practice by someone who thinks it's a cool gadget, but doesn't really know how to run a firearm. Using the off hand forces you into a fine motor control movement (hitting a small target with an unsupported hand) and puts the WRONG HAND FINGER, not anchored and secured against the pistol grip, into the trigger guard. If you took a bump or a stumble and your bolt closed, your off-hand finger is happy to pull the trigger and misfire. If I insisted on using the BAD lever with the wrong hand, I'd up my right hand around the left hand, and use the tip of my right thumb to press the release... But honestly, even that seems silly. Using the BAD lever with the off-hand is silly - it's slow, and it's a small target. The bolt release is RIGHT THERE at the tip of your (left) trigger finger. Use it. If your finger is too weak, then get an ambi charger and use that. It's just as fast, and a much larger target (gross motor control).
I've seen the "reach around" method used in the video too, and it requires just as much finger strength and a more awkward reach than the PROPER method of releasing the bolt with the left trigger finger, and it's slower. Just use the bolt release with your trigger finger, and forget the gimmicks.
"...how do you reload?..." Same way but using the left hand. Handedness makes no difference of any kind.
Anyway, AR's, like FAL's, are operated with the left hand. Safety and mag release are on the left.
Have you reloaded left handed? Or operated an AR? Safety selector and mag release on an AR are on opposite sides. Handedness does matter, especially for the AR - firearms controls, unless otherwise featured/upgraded, are designed for one hand, so a guy can't play the whole "reloading left is just like reloading right..." The mag release is the only control on its side of the rifle, the selector, bolt release, and charging handle release are all on the opposite side from the mag release. When the controls are on ONE side, it's just not possible to use the same "mirror image motion" to operate the firearm with the opposite hand. Can't get very far using your left THUMB to operate the selector as you would right handed... 'Cuz there ain't one on that side... Same with dropping the mag with your left trigger finger - ain't a mag release on that side... Common availability of ambi parts is nice these days, but while everything else can be nearly symmetrically am I, other than the PDQ, that ping pong paddle really wants to be used right handed...
