When I told my son that after 50 yards a .22 bullet begins to drop, he said that .22's can travel for miles. I told him that's true, if the muzzle is pointed high into the air. When shooting normally, the bullet continues to rise for about 50 yards, then begins to drop. At 100 yards you're just about hitting the dirt.
What we can learn from this is that if most of our shots are at 25 yards, the bullet will rise until it reaches it's peak at 50 yards, then it begins to drop. At around 80 yards the bullet will be at the same height at it was at 25. That means that you can aim to a squirrel at 25 or 80 yards with no sight adjustment.
Since my rifles were shooting high at 50 yards, they might be right on target at 25 or 80 yards. The next step it to go to the 25 yard indoor range to dial the sights in.
More ballistic curves for the .22 can be found HERE.