Is it reasonably durable?
As a relative newcomer to revolvers, I embraced .357 Magnum, the chambering that arguably compensates for the lesser capacity of the wheelgun with superior ballistics. In looking for my first .357 Magnum revolver, I naturally turned to the S&W Registered Magnum. As I searched for it, I
noted that the SAAMI advises us that 0.012" is an industry maximum for revolver flash gap. Many of the pre-war Magnums that I examined for prospective purchase approached this measurement. Some of them exceeded it. It bothered me that this excess may have attested to frame stretch.
As far as I knew, S&W forged its revolver frames from the 4140 chrome-moly and 416 stainless alloys. Whereas 416 is air hardening, although 4140 is classified as an oil-hardening steel, in a narrow section it is air hardening. Accordingly, I inferred that S&W performs a full-cycle anneal after forging prior to performing machining operations, because the material becomes hardened by cooling in the air. Factory literature suggested that S&W barrels and pistol slides were deep hardened, and in some instances also surface hardened. I wanted to know whether or not the frames were also deep hardened. I wanted to find out whether or not an S&W revolver frame was subject to plastic deformation in extended use.
Then I came across
a statement by John Linebaugh: "The frames on S&W are not heat treated thus are pretty soft." I could not think of a better authority in this technical matter. However, I suspected that at issue here is not the heat treatment per se, but the difference between the ensuing surface and deep hardening. The only revolvers that I knew to use all forged and deep hardened components were the Manurhin MR-73 and the second generation Korth. I also noted that some of the
guns chambered for Linebaugh's own cartridges used frames cast by Pine Tree Castings in 17-4PH (precipitation hardening) steel alloy and deep hardened. I surmised that the heat treatment on forged S&W frames ran only skin deep. My subsequent first-hand experience with several of their pre-war Magnums proved that that was the case.
Another contributor to this thread
wrote elsewhere a while ago:
In a head to head test with the M28, which was made in 1978 the gun I mean, I did the shoot outs last year,the Korth had a slight edge in accuracy with some but not all loads of .357. It shot more accurately with all loads of .38 Spl. that I tried by about 1/4". In shooting heavier loads (180 grain, 165 gr., 200 grain) the yoke of the M28 bent as well as the ejector rod and the gun began to go out of time and spit lead. The Korth sailed through with no problems. It is a strong gun.
It followed that an upgrade in construction methods and materials enabled a boutique revolver maker to beat Smith & Wesson at their own game. However, my interests also inclined me towards sidearms designed and manufactured for service rather than entertainment, in the way
Hans Wilsdorf paid a tribute to horological excellence by building the world's first "tool watches". So I turned towards another brand. I knew that Manurhin developed the MR73 in response to the failures of S&W .357 revolvers at the hands of the French counter-terrorist forces,
Groupe d’Intervention de la Gendarmerie Nationale. GIGN shoots a lot. They found that S&W revolvers failed in their daily practice regimen of 150 rounds of Norma 158 grain .357 S&W Magnum ammo. Manurhin developed the MR73 for extended use with this ammunition. Its torture test was abandoned without appreciable wear after firing 170,000 full power Norma .357 rounds. Numerous published tests independently witnessed this capacity. French police armorers demonstrated revolvers that remained serviceable after firing a quarter million rounds. By contrast, the N-frame S&W revolvers that had served as the original development platform for .357 Magnum ammunition, were generally expected to last but a small fraction of this life span.
I shoot
two Manurhins, a 6" dual caliber, early production revolver, and a 10¾" .357 MR73 Silhouette of slightly later Mulhouse production that I converted to double action.
That Buntline Special is by far the most accurate centerfire gun that I have ever fired. It is good to know that it will remain so for decades to come.
I have
several more Manurhins coming from Europe. I am arranging for their comprehensive mechanical and performance study in collaboration with a first-rate gunsmith and a police firearms instructor. My next project will be
a Korth.
Life is too short to shoot soft guns.
