Getting a very tightly focused beam?

I am trying to make a couple lights with very tightly focused beams. One using an XPG and the other using either a P7 or a SST-50. What is the best way to go about this? Is there anyone doing a very deep dished reflector for either that will have little to no side spill? or should I go with and aspheric lens (I will admit right here that I have little knowledge of aspheric lenses). Any thoughts on this? I have a mill and a lathe so making and modding bits is easy, just need a little direction on this.

Thanks,



Dave