With my Marlin and Rossi levers, I can get a 300gr. bullet going about 1650fps (Marlin) to 1800fps (Rossi). The Rossi can take more pressure than either a Ruger or a Marlin. They are not pleasant loads! Both those loads are in Trapdoor 45-70 territory.
Leverguns in pistol calibers are very particular as to length of the cartridge. Revolvers, not so much.