I shot a revolver in competition both tactical, and Ipsc, early on, one handed reloads were called for fairly often, my solution is a fairly complex but fast operation. Practice this with no live ammo near, and like said before, full weight dummy cartridges. You will have visualize this, if right handed, hit the cylinder latch with right thumb, with your trigger finger push the cylinder out, ( now it gets tricky ) shift your grip, quickly so that the front of the frame is resting in your palm, use your trigger finger or middle finger to press the ejector rod with the muzzle up if possible, now tuck the barrel in your pants with the cylinder on the outside, ( helps if your wearing a belt ), the gun is now secure between belt and belly, grab your speed loader and load, now remove revolver and as you bring it up, shut the cylinder with your thumb. It is actually easier left handed. If you are seated this is not going to work real well, best to do it in your lap as far as the cylinder charging go's, same if your on the ground, although between your knees will work well too.