Would still like to hear from somebody who's measured the muzzle diameter.
Why? The muzzle of my CZ 550, which I've owned since 2002, measures .605", which is considered by some as pretty skinny for a medium-bore barrel 23.6" (60cm) long. Yet it has always shot REALLY well, whether in the original clubby factory stock or the much slimmer Serengeti Rifles custom stock made five years later. Believe I have yet to try a handload that didn't shoot inside an inch for three shots at 100 yards, with many doing much better. Which, in my experience with a number of 9.3x62s, is basically how they shoot--which is of course is far better accuracy than needed for just about any use imaginable for the cartridge
My calipers are boxed up from a move, but a tape measure read right at 9/16 or 0.5625”. I don’t think the muzzle diameter is all that much of a factor compared to how thin these barrels are overall. The description at the end of the box says “24” A”, which I take to mean the same contour found on the 24” No.1-As. I own an original 1939 Oberndorf Type A in 9.3x62 and a take off barrel from the same, both having muzzle diameters of .588-590” (23.6”). Both barrels are quite heavy in the rear, step down after the sight base, then taper to the end. The Ruger barrel looks elegant, like an old long barreled 275 Rigby or 350 Rigby. I hope mine shoots as good as it looks. I may try working up your now famous Nosler Partition load, but I suspect standard velocities may be in order for this one. My rifle’s stock must be quite heavy, compared to others, as my kitchen scale reads 7lbs 10oz. This a good thing!
