Interesting thing about Ruger Old Armys (ies?) is that they are so accurately made that Ruger say you can dry fire them without the hammer quite contacting the nipple. This should be avoided in any other ML revolver as you will probably eventually crack the nipple. You do however occasionally get misfires due to this. Uncle Mikes nipples are fractionally longer but then of course you can't dryfire. Remington No 11s work best for me.