I have an original that the bore slugs .431 so I bought the Miroku hoping for a tighter bore but alas, same size! Forgot to say it's a 44 WCF. I agree it's a very slick action but when I backed off the lever and lifter springs it got a lot better. Also, I thinned the lever safety spring way down so...

I replaced the buckhorm blade with a ghost ring I made. Here's the two side be side. Look through the ring, centering target in the ring, and the bead just below target's center. So far, it's worked well for me. My eyes are 50.