Yes you can load with black powder in modern cases, in fact a few "modern cases" were black powder originally, 45-70/90/110, .303 Brit & 30-30 being the better known ones.
There are problems though.
You can't get the energy output from BP that modern powders give you, & big cases are a help, but the .303 only takes 58.1 Gr of FFFg (trust me I've tried everything & that's IT)! Because of this you get reduced velocities compared to smokeless, so you're better off loading lead bullets, not jacketed. The BP fouls modern rifling pretty fast as well so you better plan on a lot of bore cleaning. You also need to clean as for B/P not smokeless as well.
Last edited by plonker; 10-19-2011 at 02:40 PM.
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