Dimensions of the Bases
One of the most abused rules is also one of the most common and,
yet, perhaps the most important rule: the dimension of the bases.
Since home teams are required
to measure out the distances, we see all kinds of distances. The
most common is 60 feet. Occasionally we see the bases lined at
55 
feet--which is pretty short according
to the eye. These wrong distances also make a huge difference
in a game. In essence, you're shortening the entire playing field
by 20 to 40 feet.
But the fact is, the correct distance is 65 feet.
Does this seem too long? A big reason is many of the county infields are too small because the fields are overgrown and also used for Little League programs. At Wheaton Forest, for example, the 65-foot distance almost has first and third base anchored on the outfield grass.
Don't let the infields fool you.
The game umpires should walk off the distances of the bases if they look suspect. And way too many times teams cheat by just laying down the bases where there's a base mark from a previous game. What if they had it wrong, too? So to be safe, each team should have a tape measure as part of its equipment bag.
As an easy cheat sheet, here's the dimensions of the field. The back tip of the plate is the starting point for all measurements:
The baselines: All bases should be oriented so their sides are parallel to the foul lines. The measurements should be from the back tip of the plate 65 feet along each foul line. This spot determines the furthest corner of these bases. The distance from first base to second base and the distance from third base to second base should also be 65 feet.
To the pitcher's rubber: The first measurement should be 50 feet to the center of the front edge of the pitching rubber.
To second base: From the back tip of the plate, measure 91 feet, 9 inches to the second base spike.