Beretta is bringing in MR73 revolvers

[elsquid]

Question for @e_stern

Does Beretta plan on submitting one or more flavors of the MR73 for inclusion on California’s handgun roster?

Since revolvers aren’t required to have LCIs, magazine safeties, or implement microstamping adding them is fairly straightforward. ( Colt has been adding their new revolvers, and both the relatively recent 4.25 and 6 inch Pythons are available here for new dealer sales. )

https://oag.ca.gov/firearms/certifie...ch?make=151001

Thanks!

— Michael

[zeleny]

1. All major components of the Manurhin MR73 are milled on a five-axis CNC machine out of appropriately shaped hot forgings. Its cylinder chambers are finished by galetage, i.e. roller burnished after drilling. There are no MIM parts in the MR73, with the possible exception of the currently employed LPA rear sight.
2. Most Manurhin revolver models, including, but not limited to the fixed sights MR73 Police/Défense variants, the MR22 Match, the 10¾" MR22 and MR73 Silhouette, the Modèle convertible .22–.32–.38, the RMR and F1 Spécial Police, the MR93 and MR96, and the Remora 5, have been definitively put out of production since Manurhin withdrew from small arms manufacture in 1998. Chapuis makes only the adjustable sights versions of the MR73 and MR88 chambered in .357 Magnum, and the single action MR38 and MR32 Match.
3. Standard MR73 barrels are rifled with six grooves, with a right hand twist at a one turn in 476mm rate, replicating Smith & Wesson’s traditional rate of one turn in 18¾". Match barrels utilize five grooves at the same twist rate, with a bore diameter of 9.05mm. Up to serial number 39200, the bore diameter of standard MR73 barrels measures 8.96mm +0 / +0.03mm. After it, the barrels are finished to the .38 Match bore size, measuring 9.04mm +0 / +0.05mm. For obvious reasons, only the former play nice with the 9mm Para cylinder, though a few of the latter have been so (retro)fitted.
4. All Chapuis MR73 revolvers are numbered with an HA prefix. Over the past 22 years, fewer than 4,400 of them have been released in the wild. (By contrast, Korth Lollar makes around 2,500 revolvers a year.) Barring a major investment by Beretta subsidizing a great increase in production capacity, I do not expect significant discounts from the MSRP.
5. More information can be found here.

[Tuvia]

Hoping You would be along to educate us. MY Chapuis MR 38 is a SA/DA.

[OlongJohnson]

1. All major components of the Manurhin MR73 are milled on a five-axis CNC machine out of appropriately shaped hot forgings.

Thanks, that's helpful.

[LIST=1][*]There are no MIM parts in the MR73, with the possible exception of the currently employed LPA rear sight.

My suggestion of MIM was speculative, and I thought that was clear in how it was stated. I'm realistic about what MIM is and what it isn't, I won't use it as an epithet, the way many do. It remains apparent that the newer cylinder release button has changed from a machined part to some kind of casting, and that that casting is pretty rough.

1. Standard MR73 barrels are rifled with six grooves, with a right hand twist at a one turn in 476mm rate, replicating Smith & Wesson’s traditional rate of one turn in 18¾". Match barrels utilize five grooves at the same twist rate, with a bore diameter of 9.05mm. Up to serial number 39200, the bore diameter of standard MR73 barrels measures 8.96mm +0 / +0.03mm. After it, the barrels are finished to the .38 Match bore size, measuring 9.04mm +0 / +0.05mm. For obvious reasons, only the former play nice with the 9mm Para cylinder, though a few of the latter have been so (retro)fitted.

Your citing of tolerances doesn't make sense. A "+0/+(>0)" number is mathematically unintelligible. Did you mean "+0 / -0.0Xmm?"

Assuming that modification is correct, I suspect you may still be off by a decimal place:

mm inch
8.96 0.3528
0.03 0.0012
9.04 0.3559
9.05 0.3563
0.05 0.0020

Quality precision barrels are typically discussed as having bore tolerances of +/-0.0002 inch, an order of magnitude tighter than the numbers you report. Not trying to get into any kind of personal disagreement, just pursuing precision in information.

[zeleny]

It remains apparent that the newer cylinder release button has changed from a machined part to some kind of casting, and that that casting is pretty rough.

I am going by what I have seen on revolvers manufactured in Mulhouse and early Chapuis production. I await the importation of a recent Chapuis-made MR73, and will report my findings upon its receipt.

Your citing of tolerances doesn't make sense. A "+0/+(>0)" number is mathematically unintelligible. Did you mean "+0 / -0.0Xmm?"

Assuming that modification is correct, I suspect you may still be off by a decimal place:

mm inch
8.96 0.3528
0.03 0.0012
9.04 0.3559
9.05 0.3563
0.05 0.0020

Quality precision barrels are typically discussed as having bore tolerances of +/-0.0002 inch, an order of magnitude tighter than the numbers you report. Not trying to get into any kind of personal disagreement, just pursuing precision in information.

I am reproducing the official information reported here. As elaborated, “+0 / +0.03mm” means at the most 0.03" over the nominal diameter. Accordingly, before s/n 39200 the MR73 bore measures between 0.353" and 0.354"; thereafter, between 0.356" et 0.358". Yes, it’s quite a spread.

[OlongJohnson]

Thank you for linking your source!

The standard American way of expressing that tolerance would be:

9.04 +0.05/-0.00

And indeed, it is quite a spread. The implication being that any given gun must be slugged to determine what size cast should be used for good results. Any of them is likely to be fine with .357 jacketed bullets, but accuracy, pressure, etc. may vary with a given bullet in different guns.

I noticed Guillaume Tell is regarded as an authority. Do you know his background (i.e., where he would come by that information)? Is he connected with the factory?

[JonInWA]

You can pretty much take to the bank whatever information Micheal Zeleny provides-particularly concerning SIG P210s, Manhurins, and Korths. His participation here is much appreciated.

Best, Jon

[OlongJohnson]

Really quick video on roller burnishing (since Zeleny's link was to French Wikipedia):



It's a cool process.

[zeleny]

The standard American way of expressing that tolerance would be:

9.04 +0.05/-0.00

Thank you. I am a mathematician manqué trapped in the thickets of ESL and FTL. The struggle is real.

And indeed, it is quite a spread. The implication being that any given gun must be slugged to determine what size cast should be used for good results. Any of them is likely to be fine with .357 jacketed bullets, but accuracy, pressure, etc. may vary with a given bullet in different guns.

But for shooting wadcutter handguns, I hardly ever use anything but jacketed bullets, and nothing under 140gr in .357 Magnum. Going any lighter will surely erode, if not fracture, the forcing cone.

I noticed Guillaume Tell is regarded as an authority. Do you know his background (i.e., where he would come by that information)? Is he connected with the factory?

Look here.

[OlongJohnson]

But for shooting wadcutter handguns, I hardly ever use anything but jacketed bullets, and nothing under 140gr in .357 Magnum. Going any lighter will surely erode, if not fracture, the forcing cone.

Look here.

Indeed, for .357 loads in a revolver that I was unwilling to treat as a consumable, I'd hesitate to use lighter than 158gr and would probably stick with 180gr. On a gun as expensive as an MR73, I would use single-base powders exclusively, as they are widely believed to be less capable of causing flame cutting. IMR 4227 is a popular choice for that application, though it will likely leave some incompletely burned grains behind. Double-base powders like H110/W296 and Li'l Gun are for the Marlin 1894 and Contender.

In standard-pressure .38 SPL loads, I would not expect any problems using bullets as light as the 110gr XTP with appropriate powders for such a load.

I tried to look up Monsieur Tell's profile earlier, but the site requires registration to see it. I didn't decide it was important enough to register on a forum hosted in another country, etc. just to see that. Perhaps I will eventually register there if I surf around and find it to be a useful source of MR info. Thanks for the link, in any case!