Yeah - I'd estimates that on game, the 2F .577 Snider load Bob mentioned would have about the same effect at point blank range as perhaps a .44 mag. with solid lead 300's. the difference is whether the cavitation produced by the .44 mag, would outweigh the somewhat larger permanent cavity "likely" produced by the Howdah.-- it's all speculation.

If the Snider was loaded with round balls, it would have greater effect, (even though penetration would likely be less), due to the hemispherical shape of the ball acting more like a wad cutter & the attendent slightly higher velocity of the lighter ball. At very load speeds, bullet shape is very important. The pointy .577 bullet does not 'shine' in that regard. All this is simply speculation.