Depends on the ball - some don't get so big and some don't do much more than lay in their hide so yeah if you've got one on the smaller side 1500 gram or less or not very active then it would be ok.
For a bigger snake I would go with something closer to a CB70 size - (17 3/4"W x 33 1/2"L x 6"H) they seem perfect for my adults - for really big girls (over 2500 grams) - I would go with something closer to CB75s (22 3/10"W x 37 3/10"L x 6 4/5"H).
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Tosha 
"One of these days i am going to wake up..look around...and realize my place looks more like "Ace Venturas"s than my own." Coldthumb
7.33.0 Ball Python (Harry and Fluffy and gang)
1.0.0 Angolan Python (Skywalker)
0.0.1 Green Tree Python
0.2.0 Feline (Pippen and Pandora)
0.0.1 Dessert Tortoise (Pope John Paul "JP"
2.2.1 Fish (1,2,3,4)
0.0.2 frogs rescued from pool skimmer
0.0.1 lizard rescued from vicious feline