How does an revolver owner know whether his gun can safely fire +P ammo? What are the advantages/disadvantages of firing +P ammo, for either target or defense shooting? Thx

I assume you mean .38 Special +P? And what revolver? Any K-frame M&P in good condition from the 1920s or later can safely use +P. However, it really makes little sense to use it. It is more expensive than normal lead bullet loadings and tin cans, bottles, and paper targets won't know the difference. To me, about the only use for +P is to keep a cylinder full available in the event you ever face a real personal defense need. Otherwise, use the cheap stuff.

Welcome to the Forum.
The subject of +P ammo is a controversial one around here. Strong feelings on both sides, so I will tread carefully.
+P ammo is simply more powerful. Probably just a bit more powder, producing higher velocities, recoil, and a different point of impact. S&W advises not to use it in non model marked revolvers. That would be pre 1957. You can tell by opening the cylinder. If it says Mod- something it should be ok, assuming it is in good condition. Only ones that are model marked that are not good to shoot +Ps in are the early Airweights. The aluminum frame is not rated for +P. Later ones, like the M642 are.
Truthfully, it is probably ok to shoot them in later unmarked revolvers. I have a Pre M15 that I use them in with no problems.
As far as autos, I will leave that to the experts.
Jim

When did they start marking guns +P from 38 spcl? I know when I taught LE firearms in the 80's and 90's I remember the academy which generally got their info from the FBI stated it was OK to shoot +P in S&W and Ruger. Colt did not recommend it. Many of our Agents carried 37's and they were required to fire about 25 rounds each Requalification. The rest were mostly wadcutters. It was our understanding it was OK to shoot them in airweights as long as it wasn't a steady diet of them. I don't remember any of the guns marked +P in the 80's
JR

At one point, the 640 was actually marked rated for +P+.

I just checked my 642 and it was made in 97. It's marked 38 spcl. Surely a gun made then was made to shoot +P ammo.
JR

+P ammo should be reserved for defensive use. A steady diet of the stuff is tough on the hands as well as the gun. It is also more expensive,

A hit with a .22 is more effective than a miss with a .45 ACP. Lots of people, particularly casual or occasional gun users, will shoot better with standard velocity ammo and thus could be more effective with it.

All my defensive handguns are fed non +P ammo.

I wouldn't think a person would generally shoot them every time you go to the range. I would probably shoot what's in the gun and get 5-6 more out of the box for carry. I carry a 340pd in my back pocket every time I leave the house. I may or may not carry another gun. The gun is rated for 357 but my wife's 642 is not so marked. I still carry the old FBI load in all my snubbies and it is +P.
JR

General statements about +P ammunition, including this one, are generally worthless without knowing the specifics of the gun and ammunition.

Why?
For my Model 686, my barely +P minor power .38 handloads for USPSA are merely "mild .357 shorts" and you can shoot, oh, maybe 100,000 without damage or excessive wear. Hardly more strain than dryfiring.

On the other hand, if you're talking about putting the hottest +P .38 ammunition in your old USAF Model 12, you may be risking the gun and yourself.

Statements like "Never use ANY +P" are misleading and emotional, and seem ludicrous when talking about using 20,000 PSI +P .38 in a revolver designed for 35,000PSI .357 ammunition.

Same with 9mm pistols. Do you have a WWI military relic, or do you have a new S&W M&P, which can shoot +P 9mm all day.

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There are various levels of +P. The normal +P loads from Federal, Wiinchester, and Federal are somewhat milder than that from some of the Botique loaders like Buffalo Bore. But they are all within SAAMI pressure limits. Some time back, I made a posting showing advertised MVs for all the +P loads on the market. The mainstream +P loads are not much different from the standard .38 Special loads from pre-1970. There have been a number of postings addressing this. Bottom line is that virtually any post-1920 .38 Special revolver in sound condition will safely handle +P ammo. But that does not mean that it's a good idea to make shooting +P ammo a habit. In fact, it's downright stupid about 99% of the time.

Factory plus P ammo is not loaded beyond industry standards for pressure. It is safe to use in any quality made revolver in good condition.

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actual video of plus pee ammo being fired in a revolver ....



... can't chance it.

No.

No way.

GF

Not really. +P is a SAAMI rating.

Safely? For the shooter or for the gun? For the shooter, no harm is likely to ever come from shooting +P ammo in a modern gun.
For the gun, shooting over pressure loads over time could damage the gun. "Shoot it loose," as they say.

My 642's barrel is marked +P. I guess it is about 5 years old.

I have and carry one of those, but have never felt any inclination to shoot +P+ out of it.

I currently load it with the standard-pressure Buffalo Bore lead semi-wadcutter hollowpoint that matches the ballistics of the +P FBI load but is advertised as safe in any S&W revolver.

The 640 is all steel, but the Buffalo Bore load should be perfectly safe in an Airweight like a 442 or 642. Just not a hell of a lot of fun.

Of course, many people feel that standard-pressure wadcutter target loads are very effective for self defense.

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Oh well, what the hell.

The +P range is between 17,001 psi and 20,000 psi, so there can be some variation for "+P+" ammo but it they follow the SAAMI .38 Special +P spec, the won't exceed 20,000 psi.

I suspect however that many loads marketed as "+P" are only very slightly over the standard pressure specification of 17,000 psi.SAAMI standardized the .38 Special +P specification in 1974 at 20,000 psi, compared to the standard pressure specification of 17,000 psi.

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.38 Special "+P+" ammo, however varies a lot as there is no "+P+" specification and by default "+P+" is anything in excess of 20,000 psi.

In 1930 S&W introduced a .38 caliber version of the .44 caliber hand ejector and called it the .38-44 Heavy Duty. The following year companies started making high pressure .38 Special loads for it, and shortly after that Colt states their Official Police revolver was strong enough to fire these ".38-44" and ".38 Special High Speed" rounds.

Those rounds led to the .357 Magnum in 1935, but even after the .357 magnum round was developed, high pressure .38 Special rounds continued to be used by law enforcement agencies. In the 1960's and early 1970's it was an issue of political correctness, where departments and agencies wanted .357 Magnum performance but the political powers that be did not want to use the .357 Magnum round, given it's deadly reputation (these were after all the misguided "shoot to wound" years).

What resulted were .38 Special "law enforcement only" rounds, most of which were loaded to around 23,000-23,500 psi, although a couple of these rounds were loaded as high as 30,000 psi - about the level of the warmest of the .38-44 rounds. The revolvers used by these police departments and federal agencies were either .357 Magnum chambered revolvers, or they were revolvers designed for .357 Magnum but special ordered chambered for .38 Special.

The original "FBI load" fell in the 23,000 psi category and launched a 158 gr LSWCHP at 1000 fps from a 4" revolver. That's about 100 fps faster than the current commercial versions of the "FBI Load" which are held to the +P spec of 20,000 psi.

The Border Patrol and Treasury department were two other federal agencies that used "+P+" loads. IIRC, the treasury load used a 110 gr JHP at 1,200 fps from a 4" revolver.

Corbin used to sell a +P+ round loaded to just over 30,000 psi and it offered about 95% of the performance of the .357 Magnum.

In all cases, if you're going to shoot a .38-44 or .38 Special +P+ load, you should be doing it only in a revolver designed for .357 Magnum.

What OKFC05 said in post #9 makes a lot of sense.

Most responders seem to have assumed that the OP is referencing .38 Special +P. Maybe he is, but he did not specify that, nor does he even specify that he is talking about a S&W revolver. I guess we can infer it's a S&W, being this is a S&W Forum. But is it wise to make assumptions when giving safety advice?

To take an extreme case, just suppose he has a WWI S&W HE2 originally chambered in .455 Webley that has been modified to shoot .45 ACP. I believe there is a +P version of this latter cartridge, but I doubt anyone here would advise using them in a modified old warhorse.

Or suppose it is some even older black powder British Webley revolver likewise rechambered to .45 ACP. That's downright scary!

The point is that someone would have to write 5 to 10 paragraphs to cover all the possibilities for any "revolver" and any "+P" combination.

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You're shy a few manners.

This article was suggested for me when I asked a similar question. I hope it helps.
Shooting with Hobie

Thanks. Excellent article.

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I like Ike.

Always keep in mind that muzzle velocity is a variable, and can differ significantly among different revolvers firing the exact same load. This is because of two main factors, barrel length and the gap between the cylinder and the forcing cone of the barrel. There may also be other dimensional differences between guns which affect MV. On the other hand, the manufacturer's advertised velocities are those measured from standard test barrels which are not revolvers but may be vented in some way to simulate firing in a revolver.

The moral of the story is that if you feel knowing the MV is important, you cannot believe the factory ballistics. You must determine it yourself using your revolver and a chronograph. You may be very surprised at the difference between your results and the advertised MV.

"For the gun, shooting over pressure loads over time could damage the gun. "Shoot it loose," as they say."

What "over pressure loads?" As I stated earlier, mainstream +P is not loaded beyond industry standards.

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No life story has happy end.

We don't know what the actual chamber pressure is for the factory product. What we do know is that it does not (or should not) exceed the SAAMI limit established for the specific caliber. Factory pressures are normally held to values somewhat lower than the SAAMI-established limit. I believe that some loaders , such as Buffalo Bore and Cor-Bon, load to, or close to, the SAAMI pressure limits to achieve greater velocities. The big boys (Remington, Federal, Winchester) load to stay below it, but how much below, I do not know.

The current SAAMI Maximum Average Pressure (MAP) limits (Piezo gauge) are:
.38 Special ------- 17,000 psi
.38 Special +P --- 20,000 psi
.357 Magnum ---- 35,000 psi

As earlier mentioned, there is no SAAMI pressure limit standard for +P+ ammunition, just whatever the manufacture determines it should be. It should also be noted that SAAMI standards are voluntary, not mandatory, for those in the business of manufacturing firearms and ammunition.

If we're talking 38 Special, any revolver I can look at, and not think "What a piece of "junk", I wouldn't worry about shooting P+ in.

I probably wouldn't do it. There just any real reason to short of Zombies breaking in the building, but I wouldn't worry about it if I had to.

I'm perfectly happy with good old standard 38 Special for punching a hole in a piece of paper, or making a tin can jump around on the ground.

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John 3:16 .

It is not loaded beyond industry standards for +P. That does you no good in a gun not rated for +P.

Ridiculous.

Consider that most any quality revolver made since WWI has a substantial safety factor built into its construction. I do not know what MAP the .38-44 cartridge produced, but by my calculations (and I have calculated it), it likely exceeds 25,000 psi. Back in the 1930s-40s, it was not considered by either the gun manufacturers or the ammo makers to be unsafe to fire .38-44 ammunition in ANY .38 Special revolver of the time, and there were no warnings provided against the practice. And it was very likely that a great number of K-frame revolvers (and Colt equivalents to it) were used with .38-44 ammo frequently, and without damage. To me, that says use of +P is safe in about every revolver in that caliber (except for maybe those with alloy frames and those few having alloy cylinders), as the .38-44 has a substantially greater MAP than the newer +P loads do. I have fired quite a few hundred near-.38-44 level .38 Special reloads (lead bullet) in a 1920's era M&P, and nothing bad has yet occurred as a result.

You know I read this thread and those like it and I really feel for the guys who post the question of "is it safe". I know they want the best performance they can get out if their firearms but at the same time they don't want to turn their firearm into a fragmentation grenade. Unfortunately with the litigious toxic world we live in and the fear from the manufacturers and venders that should they actually (God Forbid) make a hot cup of coffee and some clown get burnt by it there is the very real possibility they will be sued and their livelihood be taken away from them.

That thought coupled with the lack of good reloading data (see litigious toxic world above) makes me very happy I have kept the manuals from when I started reloading. Now days the data has been ran thru the legal department and loads I use to this day are not even there or now greater than allowed.

I hope the OP has not been scared off and can now make an intelligent decision as to if his firearm can handle +P ammunition .

Safe? Yes. A good idea? Only under limited circumstances.

Why is this so hard to understand?

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My recollection is that in some discussion of this type (comes up monthly, at a minimum) or a discussion of .38-44 performance, someone posted an old advertisement that listed a bunch of revolvers that could stand the .38-44. Many of them were a lot smaller than I would have expected, but my memory of the specifics is lacking.

If any given round is loaded to higher pressure than another, the higher pressure round will potentially produce more wear on a firearm. That will of course vary by the firearm - an N frame will be far more tolerant than a J frame, and the actual wear on an N frame from any load you can safely put in a .38 Special case is not likely to matter.

The hot rounds will likely not be as much fun to shoot. For plinking of any kind at all with my K38, I use wadcutters (Black Hills, of course) or a standard velocity SWC. I am not trying to accomplish anything but holes where I am aiming. For personal defense, one should look first and foremost to Doc Roberts' list. I have a link to it https://pistol-forum.com/showthread....f-Defense-Ammo. This link is to a pretty serious forum, and he only has typical service calibers shown here. Read the whole post, as there is more good info of all types there. Gary is probably the premier terminal ballistics expert and researcher now that Dr. Fackler died a week or so ago. IIRC, Gary has suggested a few loads in .38, maybe on another forum that is limited access.

For many shooters, the juice is not worth the squeeze when it comes to +P. In a J frame, the increase in recoil etc from +P will be unpleasant and for most shooters (especially older or smaller ones) will impact speed and accuracy. The most important criteria to consider are accurate placement into appropriate target areas and your ability to shoot fast (shortest possible time between accurate shots). I cannot find the data compilation right now, but one should expect to fire at least 3 good shots per assailant as fast as possible before having the needed effect.

I no longer own a .38 J frame; when I did, I loaded it with the wadcutters. Only in the most odd of circumstances would it be a sole handgun (handguns are secondary weapons; rifles and shotguns, depending, are primary). A good quality wadcutter will do almost everything you will need expect for certain types of hunting.

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NHI, 10-8.

Might be a myth but I've always heard a plus p isn't much different than standard 38's from a couple decades ago. I purchase them if a deal but all my 38's are rated plus p. never have done a comparison. as far as other calibers I have no knowledge

There used to be an obvious difference in the flash/bang (whether or not it made much difference it mad in velocity) of .38 +P over regular ammo. I've haven't shot much factory ammo in years but what I have doesn't seem to have much difference in energy. More, but not much. Now if you want a tough factory load, the 'boutique' ammo like Cor Bon or Buffalo Bore pretty much gets the most out of a gun. I'd recommend looking into reloading to be able to get different loads from target to really hot for less money and to not be limited to what they have on the shelves.

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"He was kinda funny lookin'"

The principal advantage of using an N-frame revolver when firing .38-44 ammunition (back when it was a factory loading) is much more controllable recoil, due to its greater mass. That is also the downside of an N-frame revolver - more mass to lug around on your belt. Anyone who has fired .38-44 level loads in lighter frame revolvers cannot miss the fact that control under recoil is impaired, in comparison to standard or target wadcutter loads. That is one reason I am not a fan of firing anything other than standard .38 Special loadings in K- and J-frame revolvers. Additionally the cost of +P ammunition is greater and with good bullets and proper shot placement, the +P just does not buy that much improvement in performance on live targets, and no performance advantage on non-living targets.

Because it misses the point.

S&W, as an example, designs a 38 revolver to handle 38 SPC ammo. The industry std max pressure is 17k. Industry std for 38+P is 20k. So the industry doesn't make +P ammo above 20k. It is still above what the 38 revolver was designed for. Not being over 20k means nothing.

Especially important if they have nothing on the shelves!

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