My 9mm 360J is now a convertible!

[WC145]

A lot of you that have been on the forum a while are familiar with my 9mm 360J and the mods it's undergone, as they've all been chronicled here. For those that aren't, this is a quick intro to the gun and a brief discussion about the latest (and last) modification.

7 years ago S&W came out with the first run of 360Js, the low buck .38spl only version of the M&P 360. I'd been wanting a 9mm snubby for a BUG but the ones that the manufacturers had put out up to that point were all steel and too heavy. I bought one of the new 360Js to use as the base gun for a 9mm conversion project because it had the same frame as the .357mag M&P 360 - very strong, yet very light - the gun only weighed 13.3oz. This was a huge weight savings over the small frame 9mm revolvers that were available at the time (S&W 940, Ruger SP101, Taurus 905) which all weighed about 22oz, as does the newer Charter Arms Pitbull 9mm. Ruger has since come out with their LCR9, the first factory built "lightweight" 9mm revolver, but it's still over 17oz.

I had the work done by Mark Hartshorne (Pinnacle High Performance Guns). It's been rechambered to 9x23 and the cylinder cut for moonclips, charge holes chamfered, forcing cone chamfered, action job, trigger radiused and polished and overtravel stud installed, hammer bobbed and polished, made DAO, and the stock front sight swapped for a green fiber optic. I had Robar coat the cylinder with NP3 for rust resistance. The gun turned out great, functions perfectly, and with CT laser grips it weighs 13.2oz. I carried it as my BUG the last 5 years I worked in LE.

One of the neat things about these conversions is that, thanks to the 9x23 chambers and the moonclips, you can shoot multiple caliber through the same gun - 9mm, .38 Super, 9mm Largo, 9x21, .356TSW, 9x23 Win, all kinds of stuff - though I usually just use 9mm. Before anyone asks, I did not see any change in accuracy going from .38spl to 9mm. The one downside to the conversion is that you don't want to shoot .38s out of the rechambered cylinder because the cases swell and stick in the chambers and +Ps will split.

About four years ago Numrich's was selling titanium J frame .38spl cylinders and I picked one up with the idea in mind that, in the interest of even greater versatility, plus the cool factor, I'd have it fitted to the 360J so I could switch back to .38spl if/when I felt like it. Well, just recently, I finally got around to sending the gun back to Mark with the new cylinder and had him take care of it. I got it back yesterday, so now I have a 9mm/.38spl convertible J frame snubby. Shoots great with either cylinder, functions perfectly, and all I have to do to change calibers is remove the crane, slide one cylinder assembly off and then slide the other on, nothing to it. Plus, it weighs even less with the titanium cylinder, exactly 12oz..

There you have it - unique, versatile, pretty damn cool, and a great conversation piece.

[Pondoro]

That is nice.

[NCTURBOS]

How much did the original work to convert to 9mm cost?

[WC145]

It was a package price for all of the work done, but according to his website his current charge for a J frame conversion is $225. Home - Pinnacle High PerformancePinnacle High Performance | Custom revolvers, revolver gunsmith

[Shorty 45 MK2]

Very nice!

That is sweet set up and practical as well.

[BLUEDOT37]

WC145: That's good conversion. Congrats!

What was the turn-around time to have the work done?

.

[WC145]

Six months or eight months back in 2009, a couple of months this time. Pinnacle is a very busy one man shop, but Mark's work is worth a little wait.

[KLYDE]

A masterpiece. Fantastic carry package. I'm a huge fan of the 9mm revolver. Nicely done.

[John R]

How is the accuracy with the ,357 barrel and a .355 bullet?

[WC145]

Originally Posted by John R

How is the accuracy with the ,357 barrel and a .355 bullet?

I never saw any difference in practical accuracy between .38sp and 9mm out of it, but I've never shot it for groups off a sand bag. I never had any trouble qualifying with it on the MCJA duty handgun course of fire (which includes 4 heads shots at 10yds) and used it to win an IDPA BUG match a few years ago, so it's plenty accurate for social use.

In my opinion and experience, that .002" difference is a bigger deal in theory than in reality. Heck, there's probably that much variation from one barrel to the next coming off the production line. And, I've read more than once that S&W used .38/357 barrels on the 940s, just changed the rollmarks.

Because this question comes up often, and since I now have the capability of shooting both 9mm and .38spl ammo from the gun, I might just sit down sometime and shoot some groups off a rest in each caliber and see if there is any difference. In the interest of science and fun, of course.