Wow, haven't been around rimfires long? CCI has been producing "Minimag" (.22 LR hollowpoint, 38 grain high velocity) ammo since I was a kid. The magnum ammo is known as "Maximag". It's just a trademark for CCI. They also produce the 33 grain hypervelocity "Stinger" which has been around at least since the early 70s. Every discount store and sporting goods and any general store that sells .22 ammo carries the stuff.
Maximag comes in solid or hollowpoint. I like the solid for small game, doesn't tear 'em up so bad. .22 solids are my choice for squirrel hunting, too, due to the fact that a squirrel don't take much killin'. Actually, unless I'm hunting tall pines, I'll often hunt squirrel with CCI CB shorts, silent and deadly out to 25 or 30 yards.
CCI stuff is well primed, always goes bang in picky guns in my experience. It costs a little more than the bulk pack, but it's more reliable ammunition. There are more accurate loads, but not many more accurate HV loads. Of course, all .22s have preferences. The hypervelocity stinger us usually not quite as accurate due to the light bullet at the high velocities, but my 10/22 likes the stuff. So, you just have to try out different loads before settling on what works for your gun. But, overall, minimag works at least well enough in about everything I have. I keep it around.