Gun final shotgun

[aceslow11]

Does anyone know what i do to achieve the final shotgun, the one after the 7 shooter u get for beating mcgruder? I'm at 19 of 20 weapons and that's one of the acheivments, i don't know how to get it.

[chill47]

you have to complete all of the side missions 100% along with the story 100%........when you do that you get the other gun which is a cannon that looks like a shotgun and you can ride on rev. reed's armored horse.......chill