The answer depends on whether you have duct blockage. You could still get a decent flush in a clean system without it.
Though I wouldn't chance it and would definitely use Epsom Salts . You'll get a more efficient and effective flush doing it the right way with Epsom Salts . The gallbladder needs to build up pressure and then the bile and Gallstones a clean exit. You will waste less time, effort and money this way with less chance of any harm.
My advice would be make sure you take a multi-mineral supplement days/weeks in advance to avoid any complications with Epsom salt. I would also use malic acid, also milk thistle to keep your liver healthy.