Dave King and I shot with a pair of guys who used Sharps rifles on a tactical course a couple of years ago. They made hits on steel man-targets out at 900 and 1000 yards with their open-sights and big cast-lead bullets. They were good fellows and let everyone try their Sharps, I believe that most guys managed hits out at 900. They claimed that you can pull the trigger, pour yourself a coffee, have a sip, then you hear the clang.
They shot the rifles prone using two little crossed sticks with a leather strap between them that the rifle sat on, sort of like a hammock. After each shot they remove the case, then insert another case into the chamber that has a piece of elastic tubing attached to the base, then they blow a few times into the hose. Something about the moisture from their breath softening the powder residue I seem to recall. This is a definite situation where a person would want to blow, not suck unless you enjoy the taste of sulfur.
Anyhow, you should give it a try, just make sure your target is reasonably large. I shoot on another range where a club made a life-sized steel buffalo and at one point they had the buffalo setup at 1650 yards and shot at it with their Sharps rifles. Now it is at 1100 yards - pretty tough for our .308's but nice shooting for our .300's.