The advantage, beyond the original purpose as Frank mentioned, is that (when well practiced), you have a VERY fast reload and you don't need to buy a bunch of speedloaders nor do you need to carry a bunch of speedloaders as the moonclipped ammo simply goes in to the cylinder as all one piece. If you watch someone like Jerry Miculek with this setup, you'll be blinded by the speed.
Disadvantage? I found it absolutely annoying to load up moonclips and much worse to remove the empty brass later. Also, if you aren't careful, you can bend those clips and once you've done that, they'll never be the same.
For a revolver that was never designed to run moonclips -- it's a not all too cheap proposition to have someone machine your cylinder to accept them. And as was also said, longer and skinnier rounds are not nearly as easy to handle quickly as are the fat, stubby .45 Auto rounds. The .45's almost seem to find their own way in while .38/.357 need to be guided to find the holes.
Attention Brass rats and other reloaders: I really need .327 Federal Magnum brass, no lot size too small. Tell me what caliber you need and I'll see what I have to swap. PM me and we'll discuss.
Last edited by Sevens; April 23, 2013 at 01:52 PM.
Reason: fix minor detail