I do the same, but I can't compress the round underneath far enough to get the other in, without using a round to finish pressing down the lower round.To load the magazine, I use my left hand to push the cartridge in the top of the magazine down, then my right hand to slide the next cartridge in. It doesn't work well to push the top cartridge down with the incoming cartridge.
I'm gonna mess with loads a bit, and tinker with action screw torque. I'm happy enough with 1.5" or so. longest shot on game I'll likely take is 300-350yds. For plinking and target shooting it would be nice to get it tighter than that, but it's not necessary.