Meh not my list but I admit I don’t favor many older films.
Absolutely criminal not to have casino on there. City of god was a good shout though.
Most people here won’t be up for it but Belly is as good as any.
Others for me
Reservoir dogs
Menace II society
Paid in full
Layer cake
Snatch
I’d argue No Country for old men…what’s more gangster than Anton Chigurh