Baby BPs will poop quite a bit. Older snakes eat more substantial meals and have a bit over a slower metabolism.
A four month old BP is still eating young rodents which means the animals are getting digested quicker. Some bps will grow faster than others which means a faster metabolism....and more poop.
I have 3 siblings who are 3 radically different sizes. 210grams, 140grams and 60
grams. The biggest one is the biggest poop machine. He is always hungry and never misses a meal.