.38+p vs 38 Special

[nailer]

I have a S&W 442. It shoots 38 or 38+p. The 38 +p is "plus power."

[knight0334]

I have a S&W 442. It shoots 38 or 38+p. The 38 +p is "plus power."

+P means: overpressure.

You can have overpressure with less power. But it's the pressure that determines it's suitability for a given gun.

[Guns N'at]

.38 Special +P has a higher rated avg max pressure over standard to achieve higher velocity for a given bullet, over the standard loading as dictated by SAAMI; the body in the US that regulates these type of things, along with chamber specs, etc. The actual increase has changed over the years, but is anywhere from 1500-3000 psi increased max avg pressure over the standard max avg pressure for .38 Specials 17,000 psi, depending on which figure is used.

To put this into some rough perspective, a 158 grain lead bullet not exceeding the standard pressure will have a muzzle velocity of around 750 fps from a 4" or so revolver using a .006" cylinder gap. The same bullet loaded to the higher of the two +P spec will run nearly or over 900 fps. 9mm ammo can also be loaded to an SAAMI rated +P spec that is 38,500 psi, but when you see +P+ in .38 Special or 9mm, this is an arbitrary designation, not supported or sanctioned by SAAMI. +P+ max allowable pressures are what the ammo maker sets to whatever level they want. Many times +P+ 9mm will be called "SMG" or "Carbine" ammo, but has been used in plenty of service pistols too. .38 Special +P+, and even +P can often have a stern warning saying "for police use only", but can be bought almost anywhere.

Not all high velocity .38 Special ammo necessarily has to be +P, even with the designation, as +P IMO has become a pretty nifty marketing tool over the years. "Plus V", for plus velocity may be more accurate in some situations, but I guess +P sounds cooler? If you are a reloader, +P data does exist, and one of my favorites is the current max Alliant data using a 158 LSWC HP, using Power Pistol powder. This "FBI load" is very hard hitting, and avgs 927 fps from my 3" S&W Model 60.

Lastly, using +P in a soundly built non +P revolver is detrimental by virtue of added pounding of the frame/cylinder and parts that relate to them from added recoil, not by believing that using +P rounds in the non +P rated revolver will self destruct with its use. Any .38 Special revolver proof tested, has survived pressures that far exceed even the higher 20 psi +P max rating.

[tommy610]

I think there is sometimes confusion over the word "special", and the OP may have been addressing that. "38 special" is the name of the caliber being discussed. For a 38 special caliber gun, it always takes "38 special" rounds. Don't feed it any other "38" stuff like "long" or "short" or "colt"... it must be "38 special". Then, you can vary the power with the +P, etc, as discussed here.

I'm not trying to dumb this down, but I recall being confused about this when I first bought a 38 special revolver and was shopping for ammo.

[Guns N'at]

I'm not trying to dumb this down, but I recall being confused about this when I first bought a 38 special revolver and was shopping for ammo.

I see where you are coming from... When I sold Guns/ammo, I would have folks flat out tell me I was wrong, when I suggested they might try shooting .38 Special ammo out of their new .357 Magnum... "what the hell you talking about man, the damn gun says .357 Magnum"... OK bud, all magnum for you. .38 S&W vs Special was another whole kettle of fish.

[knight0334]

I see where you are coming from... When I sold Guns/ammo, I would have folks flat out tell me I was wrong, when I suggested they might try shooting .38 Special ammo out of their new .357 Magnum... "what the hell you talking about man, the damn gun says .357 Magnum"... OK bud, all magnum for you. .38 S&W vs Special was another whole kettle of fish.

Lets throw in the .38-44 also if you want to confuse people.. Most people have no idea as to what it is.

[Guns N'at]

Lets throw in the .38-44 also if you want to confuse people.. Most people have no idea as to what it is.

That's a good one. Interesting to note with our discussion of .38-44, how for instance my 1950's Lyman "Handbook of Cast Bullets" deals with ammo in this instance and intended guns (N frames). Never is the word "pressure" added anywhere, not extra pressure, higher pressure, nothing. Lyman writes "38. Special High Velocity (Heavy Frame Guns Only)"... If you like 1380 fps .38 Special wadcutter data, this book is right up your alley .

[w30wcf]

velocity comparisons....
158 gr. bullets - factory ballistics / velocity in my 6" Ruger .357

.38 Special.............755 fps
.38 Special +p ........890 fps /... 971 f.p.s. (R-P)
.38-44 ................1,115 fps / 1,105 f.p.s. (Rem-Umc)

The .38-44 was first listed in the Rem-Umc 1932 catalog and last listed in 1940. By that time the .357 magnum made the .38-44 obsolete.

The .38-44 loads referenced in the 1950 and other Ideal / Lyman catalogs in that time period exceeded the original .38-44 factory ballistics.

w30wcf

[Giddyupgo]

.

To put this into some rough perspective, a 158 grain lead bullet not exceeding the standard pressure will have a muzzle velocity of around 750 fps from a 4" or so revolver using a .006" cylinder gap. The same bullet loaded to the higher of the two +P spec will run nearly or over 900 fps. 9mm ammo can also be loaded to an SAAMI rated +P spec that is 38,500 psi, but when you see +P+ in .38 Special or 9mm, this is an arbitrary designation, not supported or sanctioned by SAAMI. +P+ max allowable pressures are what the ammo maker sets to whatever level they want. Many times +P+ 9mm will be called "SMG" or "Carbine" ammo, but has been used in plenty of service pistols too. .38 Special +P+, and even +P can often have a stern warning saying "for police use only", but can be bought almost anywhere.

If you are a reloader, +P data does exist, and one of my favorites is the current max Alliant data using a 158 LSWC HP, using Power Pistol powder. This "FBI load" is very hard hitting, and avgs 927 fps from my 3" S&W Model 60.

Can you advise which 158 LSWC HP you are referring too? I am very much interested in this round with Power Pistol. I was looking at some Speer bullets today that fit this discription. Would this be the same bullet you are using? I too have a 3" S&W 60 and this seems like a sweet combo.

[Guns N'at]

Can you advise which 158 LSWC HP you are referring too? I am very much interested in this round with Power Pistol. I was looking at some Speer bullets today that fit this discription. Would this be the same bullet you are using? I too have a 3" S&W 60 and this seems like a sweet combo.

Sure Giddyupgo. I use either Speer 158 grain LSWC-HP, or Hornady 158 LSWC for the Alliant Power Pistol load... Sweet it sure is out of a 3" Model 60! The Speer LSWC-HP bullets I use are from a large purchase 20 years ago, so I hope they have not changed how they perform today. Here is a link from Midway showing these Speer bullets:

http://www.midwayusa.com/product/258...int-box-of-500

The Speer bullets seem to use a softer alloy over the Hornady bullets in my experience. Shown on the right is this Speer bullet that had an impact velocity of about 900 fps compared to other handloads tested in other calibers, and performance IMO is very good.



I was out shooting light weight cast bullet handloads in my .38 S&W Webley MK IV yesterday, at "Webley-esque" velocities, and these .38 Special +P 158 grain loads really let you know when you switch guns.

Pop Gun:



Serious .38 Special +P thumping:



I think you will really like the results you will get with this Speer/PP combo.