Is +P okay in older S&W 642?

[soonerboomer]

My older 642 DOES NOT say "+P" on the barrel like the newer ones. Is it okay for me to shoot +P ammo in this gun? While I'd prefer the hotter round for carry, I love this gun and would not want to risk damaging it.

I don't know when my older S&W 642 (SN: BKB2xxx) was made, I would guess it was sometime in the late 80's/early 90's. If you can find out, I'd love to know.

Thanks

 

[ArchAngelCD]

The best way to know for sure is to write S&W. Give them the serial number and they will tell you if you can safely shoot +P ammo from it.

 

[rcmodel]

BKB serial dates to 1992.

S&W will tell you no +P if you call them.

Everyone else has been using +P in J-frame S&W's since it was invented with no problems.

rc

 

[ArchAngelCD]

S&W will tell you no +P if you call them.

Everyone else has been using +P in J-frame S&W's since it was invented with no problems.

rc

I agree because the current ammo listed as +P by the manufacturers is nothing more than the stout standard pressure loads of the past. I didn't want to be the first to say it but I do agree.

 

[dairycreek]

My gunsmith is a pretty knowledgeable guy and his answer (specifically in relation to the 442) is that the 442 will take +P ammo with no particular problem involved. He then follows with the following admonitions. First, any gun exposed to increased pressure loads, will, over time, face additional wear and the high probability of mechanical problems. So, the use of high pressure loads will decrease the effective shooting life of a firearm. Of course, how much and how often the loads are employed is a major factor.

Second, the idea of using +P loads is to effect higher velocity. But, you may or may not get the desired increased velocity! That, is highly dependant on the particular gun and loads used. A little research with a chronograph will help you to find out if you do, in fact, get the increased velocity you seek. However, while you may not get the desired velocity increase you will get the increase in pressure and attendant wear.

Personally, I avoid +P loads as I don't think they really give you what you want - but that's just me.

 

[MJ2008]

S&W

I carry a S&W Centennial for the last twenty years. Its my authorized off duty weapon. It doesn't say .38 +P on the barrel. Just .38 S&W Special. I have fired nothing but +P thru it since day one. Originally 158 grain semi wadcutters. Now only 135 grain Gold Dots. Has gone bang each and every time. If it couldn't handle +P pressure my job would never have authorized it nor would they let you carry it today.

 

[SaxonPig]

Since +P is loaded well BELOW maximum allowable pressure limits for the caliber it will cause no concern whatsoever in a well made gun.

S&W ALWAYS says "no" when asked about +P in any of their guns because this is what their lawyers tell them to say.

 

[Gary A]

I carry a S&W Centennial for the last twenty years.

Is it a Model 640 with a steel frame or a x42 with an aluminum frame? I'm betting it is a Model 640, right? Speer used the Model 640 to test their 135 grain SB Gold Dot.

I'm thinking that most people would agree that +P ammo in even an older steel J-frame would not be cause for concern. Ayoob used to argue that the shape of the Centennial made it stronger than the others and that is why it was chosen for the first .357 J-frame (in steel, of course). Where the differences of opinion come to play is in regard to the aluminum-framed J-frames and whether shooting of +P rounds in some undetermined number might cause the older guns to experience stretching of the topstrap. If so, over time this would cause the revolver to misfire and eventually stop firing reliably altogether.

I don't think anyone argues that the gun is not "safe" to fire with +P for defensive purposes. The argument is simply over how many +P would damage the older aluminum J-frames.

Depending on how each of us answer those questions for ourselves helps to determine what ammo choices we make.

 

[rcmodel]

Back when the +P rating was new, Dick Metcalf & Shooting Times did a 5,000 torture test on two S&W air-weight Chiefs Specials.

After 2,500 rounds each, there was no measurble change in head-space, cylinder gap, or anything else.

The only measurable change in the guns was they were both getting slightly higher velocity, and shooting slightly smaller machine-rest groups.

rc

 

[MJ2008]

S&W

Its the stainless steel 640. Before this was an approved weapon they had approved another model(possibly the 60). Some of the revolvers developed cracks and they were taken off the approved list. Past ten years or so they only authorize semi auto 9mm. For the more senior members its grandfathered for .38's. If its an alloy revolver there could be some concern. I doubt a limited number of +P's would be an issue but Im not a gunsmith. The Colt Cobra's were also able to fire a limited number of +P's but were recommend to be inspected by Colt after a number of rounds(1000 I think). Newer S&W alloy frame weapons made from their scandium dont have this issue.

 

[CDW4ME]

rcmodel:
"Back when the +P rating was new, Dick Metcalf & Shooting Times did a 5,000 torture test on two S&W air-weight Chiefs Specials."

I actually have the article it's in the May 1997 issue. He used his own model 638 for 2,500 rounds of the test; he said the gun was about 2 years old at the time.

I have a model 638 and 442 I purchased new around 1993-94. Approximately the same age as the 638 used in the test. S&W started putting 38+p on the barrel just a few years later. I always wondered if they actually changed the metal or just decided the gun could likely take the "typical" number of rounds the "typical' buyer would shoot.

I've never shot a single round of +p through either revolver, but apparently a limited number of +p rounds really wouldn't matter.

 

[ArchAngelCD]

S&W started putting the +P rating on their J frame barrels when they switched over to the slightly larger Magnum frame in 1996. (I think it was 1996) Pre-lock +P rated Airewight J frames include the M37-3, M637-1, M638-3 and M642-1. The M36-9 is also rated for +P ammo and is a pre-lock revolver.