Snoop was often high on set and 50 admits he tried to reason with his fellow rapper in his trailer.
"I'd tell him, 'Don't smoke,' and he said, 'Why do you wanna ruin my day? It's legal. Why do you come here? Why do you wanna bother me?' "
"He's not even getting high - you've gotta be sober to get high. He's just sustaining his feelings... but (he nailed) every line... He said, 'I've been doing this since Jaws was a goldfish!' "
50 also put another pal, Eminem, through his paces on set.
"Black Mafia Family" is inspired by the real-life story of the Detroit crime family led by Demetrius "Big Meech" and Terry "Southwest" Flenory.
Eminem will play real-life drug dealer Rick Wershe, Jr. who was arrested for cocaine possession and handed a life sentence. He was paroled last summer (20), aged 50.
In the "BMF", the Slim Shady and Snoop Dogg will join the likes of La La Anthony, Serayah, Tyshon Freeman, Stormy Meriweather, Michole Briana White, Ajiona Alexus, and Eric Kofi-Abrefa.