I have just got some WTB Bronsons (standard non TCS) and am trying to set them up tubeless. They are seated at the bead, you have to snap them out of the bead hook to get them off. There is loads of stans swilling around in them. But air keeps coming out round the bead.

Anyone had this with other tyres and got any tips about what to do?

try some gaffer tape and run it up the sides of the rim to make the seal tighter, it worked on my fat tyres with a ghetto compressor, or if you havent tried a compressor try that maybe.
sometimes its a good idea to blow the tyre up with an inner tube to seat the bead harder, then unseal one side only and take the inner tube out.
fingers crossed

You can try seating them with an inner tube as above, I found heating the tyres up (in the sun preferably, hot water works too but is more difficult to retain the heat) helps sealing and a washing up liquid water mix used on the bead might help too.

have just got some WTB Bronsons (standard non TCS) and am trying to set them up tubeless.

Do it properly. Use tubeless ready tyres/rims.

Bikeneil, they are tubeless rims. I object to the price of tubeless tyres.

They were seated with a tube first, have washing up liquid all over them and still not playing ball.

CO2 pump, then shake them like a maniac should do it, i have maxxis non ust tyres for the same reason, works a treat!

Success! A wrap of tape and they work with the ghetto inflator. thanks Lester.