If we are talking about work done by smiths, on top of action job comes custom made cylinder. BTW, decades back I found in an article that custom smiths were able to adjust timing on S&W revolvers in such extend that top shooters won or ended up very high in bullseye competition. I guess they first selected revolver to make sure that bores are uniform and positioned properly.
As BSME, worked half of my carrier in aerospace industry, specialized in tooling and manufacturing (example; main gearbox for military helicopter) I can tell you that could be considerable difference from plant to plant in quality, even all of them used modern CNC machines. In addition to quality on M73, I found that certain production of this revolver is not as glorious as we generally assume. They had their ups and downs. Apparently, earlier guns were better built than when production was just transferred to Chapuis. I am aware that this video will be "opening can of worms" because it states "
MR73 The unbreakable revolver BROKEN":
Take a look at 1:34, pay attention to aft end of barrel. IMO erosion clearly shows that noted revolver just cannot take "150 rounds of full power 357 Magnum ammo every day" as claimed. Shooter was accused by vendor of shooting "dangerously overloaded ammunition". Regarding reloaded 38 Special ammo, he was also bashed in comments ""professional" reloaders destroyed a very expensive revolver".
First, I cannot imagine that anybody will load 38 Special on a such level that will destroy the gun built for 357 Magnum. Second, just doesn't make a sense to purchase such expensive revolver and shoot dangerously overloaded 38 Special or 357 "Thermonuclear". Any shooter will immediately notice if 38 Special is strong as 357 Magnum or stronger. Heck, if I want to shoot very hot 38 or 357, I will take large frame revolver made for 44 Magnum or 454.
On the end, I would like to make clear that, if money isn't the issue, I will purchase M73, but new production, under Beretta umbrella. However, most likely I will get stainless Korth 357 first
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