You also need to think of it this way....
If you breed your 50% male to your 50% female and you get all normals, what do you know about your snakes? <b>NOTHING</b>.
I would do exactly what everyone else has said... Get a 100% het male.
That way you at least know the offspring are 50% poss hets and can then breed the females back to their father (not a bad thing, especially if you only do it a few times).
Now, if your 50% female turns out to be a het after all, you saved yourself...
1) 100's of dollars.
2) 2 or 3 years of waiting.
3) 348 headaches trying to figure out your odds each successive pairing, each successive year.
4) Holding back every single offspring on the off chance they are actually hets when there's a chance NONE of them are hets because the parents weren't hets to begin with.
There you have it.... But the choice is yours.