GTP hybridization projects are notorious for being difficult to get successful offspring from. Slug clutches, eggs that fail halfway through.. it's tough. Do some reading on GTP egg incubation, incubating GTP eggs is also notoriously more difficult than many other python species.
One thing is for sure, any offspring from a ball x gtp would likely not be mistaken as anything else, and that's what I like in hybrid projects!!
Hybridizing very similar species makes for more confusion than hybridizing drastically different species, and tends to make for the most spectacular successes when they occur.
For examples of distant hybrid successes, please see:
ball x woma
ball x burm
carpet x borneo
For examples of hybrids I consider failures (defined as, once you see the offspring, you think "well, that wasn't worth the effort"):
ball x angolan
blood x borneo
rhino x gaboon (this one even occurs in the wild, but I much prefer the distinct species' looks at the extreme furthest edges of each others' range)
Good luck, don't count on succeeding even on your fourth season attempting this cross. Try it enough and change things up when you encounter failure, and you might get a few eggs to go full term and produce healthy hatchlings.
Coming from an STP perspective.. i have seen some amazing blood borneo crosses... but im biased. Check this out:
http://thereptilereport.com/coastal-carpet-x-black-blood-python/
Last edited by sissysnakes; 10-09-2012 at 07:13 PM.