I'm not entirely sure what you mean by "SMACK" sound. Usually drumline snares have a really tight, staccato sound. They use this type of sound so that the individual notes in a roll or drag can be heard.
Hard rock drummers usually go for a looser, "sloppier" sound. This gives more energy and power to the sound of the snare. So when you say that you are tightening the lugs as much as you can, you are actually doing the opposite of what you should be doing. If you really cannot tighten the heads any more, the heads might be stretched out.
There are many ways to tune a snare drum.
This is how I tune my snare:
1) I tighten the batter head pretty tight, but not too tight. I am able to push down hard on the head with my thumb and see the head move a little bit. If you can't push the head down at all, it is too tight. I also make sure that the head is tightened evenly at each lug by tapping the head near each lug with a stick. The batter head needs to be tight enough to get the sticks to bounce well.
2) Then I tune the resonant head. For the bottom head, I tune it a little lower than the batter head. Make sure it is tightened evenly, and that it has a lower sound than the batter head.
3) After the heads are tuned, I adjust the tension on the snares. The tightness for the snares can vary a lot. I even change the tightness depending on what song I'm playing. Usually I tighten the snares a little looser than the point where the snares would simply snap when I hit the head with a stick. This allows the snares to rattle just a little bit when I strike the head. Just play around with the snare tightness until you find what you like. Start loose, then tighten untill you like the sound.
If you want to get rid of some of the ringing sound, you could take 4 inch pieces of duct tape and fold the center of the tape together. Then, take the unstuck ends of the tape and stick them to the drum head somewhere near the edge. You should have about a 1 inch flap sticking up and two 1 inch pieces stuck to the head. You can even put a few pieces on each head if you want to, just put them in a spot that won't get in the way of your sticks.
If you follow this tuning, you should get a nice CRACK sound out of your snare, but I'm not sure if CRACK is the same as SMACK. :)