So it turns out that I -did- end up getting a Blackhawk (45 colt blued 7.5") and one of the things that bug me are the cylinder holes not lining up with the loading gate. I know the New Vaquero and flat top blackhawks have the new little plunger which lines up the cylinder for you. I would like someone if they have a minute, to mic out the little plunger for me if they wouldn't mind?

I am making a jig to help locate the hole center incase people want to drill the frame on the Blackhawk to add the parts. I have it mostly done but need the specs on the plunger to make sure things are lining up right.

If anyone has one, can they measure width and length of both diameters for me? Here's a picture of it I snagged from google. It has a set screw on the other side in the hammer channel and a spring inside too.

Click image for larger version.  Name: mid-frameindexingplunger_zpsf91f670d.jpg  Views: 17  Size: 44.2 KB  ID: 246817

If all goes well and it does manage to line up, it'll make adding this feature to every ruger a snap without needing a super competent gunsmith to locate and drill the holes.