I've put quite a few rounds through my Browning Buckmark...the worst brick of ammo I ever bought was a brick of Aguila. Every individual box of 50 would give me at least 4 or 5 duds. I'd purchased a couple before, and had no problems, but that one bad box put me off their brand. It might have been stored wrong before I bought it, or maybe it was just a bad run, but that sticks in my mind and so I went back to the bricks of Remington and Winchester. A friend of mine only buys CCI, and he has had exceptional luck with those, don't know that I've ever seen a FTF with them while at the range. When I'm tired after shooting the larger calibers, I always shoot the .22 last. I'm still good with it at that point, plus the ammo is cheap, so it's a nice way to finish the range session. If nothing else, the .22 should be easy to keep on target, even if you're fatigued...
I've grown partial to 22wmr over the past few years... taken most "varmints" with 'em... cheaper than .223 but not the wide range of options as 22lr... would wonder if there is a significant difference in ballistics between lr and wmr...
I have a 30 round mag in Rugger 10-22. So I would assume that 30 rounds would make an inturder slow down. I have many firearms in my collection, and I look at it this way, if a person only has a .22 for protection, that is better than having nothing.