Here's some pics of the test guns I mounted the sights on.
Gun #1 SB2 in .357 Maximum with muzzle diameter of .750".
Front sight had to be .580" tall to get a point of aim zero at 100 yards with the peep at the lowest setting. This is .115" taller than the factory original, but at the low end for the Williams base shown in the photo.
Load was 18grs. H110 with a Hornady 180gr. XTP. I don't know the exact velocity because I don't have a chronograph. I figure around 1900fps.
Gun #2: Huntsman .50 cal with muzzle diameter of .890"
The front sight used was a clamp-on deal from MMC it was approximately .500" tall to get a 50 yard zero. I had to screw the peep up 3 half turns to get proper elevation.
The load was 95grs. Pyrodex RS with a .44cal 300gr XTP in a sabot. Velocity was approximately 1550 according to the Hornady website.
The front sight shown in the picture is the factory original, it is .590" tall and will require the rear to be elevated some more.
The dimension for a proper zero with the .357 Max was .955" from
the top of the post to the center-line of the bore.
Smaller diameter barrels will require tall front sight bases, fat barrels will require shorter ones.
Also;flat shooting cartridges will need taller front sights than slow, looping cartridges.
I did not check the range of windage adjustment on the sight because it was way to windy to get accurate data. But I would recommend that you make sure the front blade is timed up with the rear sight before you try to zero.
Unfortunately, H&R's quality control is lacking; neither of these rifles have holes for the front blade that times up with the scope base holes worth beans. This may require the front sight to be soldered on to better time with the rear mounting holes.
Overall I'm very pleased with the sight, and will be using it for deer hunting this year on the .357 Maximum.
Feel free to start ordering them.