A trick that has worked for me over the years is...

Put the females in a 32 qt tub (preferably the blue ones) use cypress mulch for bedding. Put a large plastic flower pot bottom (the things used to collect water from flower pots) in for a hide box. It should take up most of the tub. Put a smaller water bowl in. There should be almost no room for them to more around outside the hide. They will cram into different spots in the tub though. Leave tub in a dark area, with very low traffic. Do not check on them for 3 weeks to a month. After 3-4 weeks drop a large mouse or sm rat in there with a few pieces of dog food (so the rat dosent eat the snake) in the middle of the night, leave the rat in till the morning, if its still in there in the morning take it out and wait another 2 weeks (african rats do work the best, then mice, then rats). Do not use light or a flashlight in the cage. They almost always take food this way. Continue feeding like this for 4-5 weeks (mouse in at night). Then you can move them into a rack and they usually take off just fine.

Hope this helps
Jon