Um.. as to the peacemaker rifle? Look up the Metal Storm system. With a rate of fire of around a []
Um.. as to the peacemaker rifle?
Look up the Metal Storm system. With a rate of fire of around a million rounds per second (Not a typo.) They definitely could build a rifle that fired all the shots in less than a second and now blow up.
Now it wouldn't cause the burning effect, your opponent would be just really really full of holes. And it would be a pain to reload, you'd likely have to replace the entire barrel to reload.
But the rate of fire is realistic... ish.