S&W 442 Failure

[Alpha Sierra]

While I wouldn't put it past S&W to use MIM in such an important area as the firing pin bushing, AFAIK these parts are still made from real steel.

MIM is not a material. It is a forming method.

I have no idea what alloy that bushing is made of, so I'll use an example of a material I am familiar with: 17-4 PH stainless in the H900 condition. The mechanical properties of it are identical whether the part is made through the MIM process of machined out of stock. The only change is about a 1 to 2 percent lower density to MIM vs wrought.

Terms like "real steel" don't add much to the technical discussion. However, parts made through the MIM method have certain design rules/guidelines that need to be followed to prevent premature failures, just like every other metal forming method out there.

[LSP972]

The mechanical properties of it are identical whether the part is made through the MIM process of machined out of stock.

Terms like "real steel" don't add much to the technical discussion. .

But are the CHEMICAL properties the same? IOW, does it withstand heat/erosive actions the same?

As for not adding much to the technical discussion... excuse me all to hell for being a bit old-fashioned, and not an engineer.

.

[Alpha Sierra]

But are the CHEMICAL properties the same? IOW, does it withstand heat/erosive actions the same?

The mechanical, not chemical, properties define what you are asking, so yes, both will withstand heat and erosion the same.

Chemically (the % of each element that makes the alloy), they are also the same or else they cannot be sold as 17-4 PH.

As for not adding much to the technical discussion... excuse me all to hell for being a bit old-fashioned, and not an engineer.

The MIM bashing gets old.

[ST911]

Here are two views of the 642 I mentioned earlier in this thread. Serial number CBW#### has been in service a few more years than the 442, and has about 2k rounds on it. The 642 and 442 have fired similar types and quantities of ammunition, and used the same cleaning products. Cleaning products are primarily WS-CLP or Slip. Also of note, after I acquired the 442, the carry and use of either was pretty random.

[Alpha Sierra]

I wonder about the length of the firing pin in that 442.....

It might have been piercing primers.

[ST911]

This just in: Another 442, same DCU serial alphas 4000 apart from mine. This one looks just like mine did when the damage was first observed.

[Alpha Sierra]

Interesting.

Batch of out of spec long firing pins?

Batch of bushings with incorrect heat treatment, or incorrect material?

The fact that the frame on the first example was compromised at the same locations as the bushing damage still has me guessing some sort of gas impingement like pierced primers.

[LSP972]

Skintop… I have four J frame Centennials; two pre-95 and two post-95 (1995 is the year they started changing the frame design forward of the recoil shield). All have been fired quite a bit, especially the .357 M-360PD- albeit that one almost exclusively with .38s.

Your revolver, and the other one you posted a pic of, appear to have "normal" length firing pins.

I have pierced a few primers, on reloads where the brass was basically worn out and the primer very loose in the pocket. My agency had a Camdex machine, loaded all of our practice .38 on it, and re-used the brass until it failed; normally via split case mouths, but in other manifestations as well. When a primer was pierced, the report was different, the recoil FELT different… IOW, the fact that something untoward had occurred was immediately apparent. There were prominent smudges on the case heads and recoil shield, and in one instance I had to slap the cylinder open with the heel of my hand because the displaced metal of the pierced primer was binding against the hammer nose bushing (let me pause here and say that the S&W revolvers which featured a firing pin attached to the hammer called that part the "hammer nose". The Centennial originally had a hammer so equipped; not sure when they went to the inertial separate firing pin, 1968 or thereabouts I think).

That's a long-winded way of saying that I'm pretty sure if you were piercing primers you would have noticed it at some point.

Note that erosion at the other end of the cylinder, at the gap where the cylinder face meets the forcing cone of the barrel, is quite common… known as gas cutting or flame cutting, where the underside of the top strap is eroded. My old issue M-66-1 has a noticeably deep "trench" there, from many, many thousands of rounds; quite a few of which were full-patch magnums. The Ti-Scan AirLite magnum revolvers have a small steel plate inlet in this area to prevent such, as the scandium alloy of their frame is quite susceptible to flame cutting of this nature.

Anyway, we're talking a M-442 here, the standard aluminum alloy frame that is good for quite a lot of standard pressure .38s. My point is, while I have seen a large number of S&W revolvers with gas-cut top straps, I have NEVER seen one with the damage yours and that other one show. And seeing as I was once responsible for the care and maintenance of almost a thousand S&W revolvers, I've had more than a few of them in my hands.

I don't know for sure what the cause is. If I had to make a diagnosis, I would go with "bad metal". The fact that the factory offered to replace the revolver, free of charge, without asking any questions of you first, tends to support my theory that THEY know what the problem is, and it ain't your ammo.

.

[mosin46]

not much help,but,had a similar issue with my AR. my smith went thru it and the best but not only answer was a pierced primer. no harm to the gun but the burn looks similar.

[ST911]

Replacement is here.



SW 442-1, sku #150544, ser# CWZ####, born 10/31/2014

The good: Gun is sans lock as requested, a true no-lock and not a factory plugged variant. This gun has an extremely smooth trigger, one of the best I've seen on a NIB J-frame in recent years. Prior to its arrival, I had dug out a spare Apex kit, but will leave it alone for the time being see what more a little dry fire polish will do. I took it to the range and fired 50rds of AE 130gr FMJ and 50rds of Fed RTP 130 FMJ, no issues. The gun shot POA/POI at 7 and 10yd on small bullseyes, and stayed on a head at 15yds and high chest at 25yds. That's good enough for now.

The bad: The left stock panel doesn't have enough relief for a speed loader to align and cartridges to feed. Every reload attempt with Safariland Comp 1 and HKS loaders resulted in rounds hanging and much fussing to get the gun back in play. A replacement set will be mandatory for my purposes. Further, the stock screw is a hex head instead of a slotted screw, adding another tool to the range kit.

The timeline:
8/3-8/8, misc comms with LE rep
8/11, call tag received from factory and gun shipped
8/27, contact from factory, gun unrepairable, need FFL for replacement
8/29, FFL sent
9/8, status check requested - no response
9/22, status check requested - no response
10/15, status check requested, replacement allocated, should receive 10/20-10/24
11/3, status check requested, gun is shipping that day, tracking number provided
11/5, gun delivered