Rookie question! .32 revolver vs .32 ACP?

[Biff Tannen]

Forgive me, I’ve done the research but can’t make heads nor tails of it.
Please advise- what’s the difference between the ammo of a .32 revolver and a .32 semi?
Suggested Links???
They say there are no stupid questions, but this may be the acception
Thanks, all! Stay safe and God bless!!!

[Sevens]

".32" covers a slew of different cartridges. The .32 ACP is the most common ".32" used in semiautomatic pistols. Typically, it's a 71gr jacketed round nose slug in a short, semi-rimmed pistol case.

".32" in a revolver is typically going to be one of the four most common... .32 S&W, .32 S&W Long, .32 H&R Mag or .327 Federal Mag. Their relationship to each other is similar to the .38 Special's relationship to .357 Mag. Longer, higher pressure... shorter, lower pressure, and the shorter ones can safely be used in guns chambered for the longer ones. These are all rimmed revolver cases.

[burrhead]

what’s the difference between the ammo of a .32 revolver and a .32 semi?

The simple answer is the revolver round has a rim, ala the 45 Colt, and the 32 auto is rimless like a 45 ACP.

[Rothdel]

Originally Posted by burrhead

The simple answer is the revolver round has a rim, ala the 45 Colt, and the 32 auto is rimless like a 45 ACP.

32 acp has a rim. its smaller than a typical revolver round but it is there. Thats why this debate can be confusing. A 32 H&R and a 327 federal revolver can chamber and sometimes shoot 32 auto. You should not attempt that in a 32 long or short firearm.

I don't know why some firearms wont successfully fire a 32 auto all the time? Not even sure if that is accurate. I have 3 revolvers in 327 federal and all are 100% reliable with 32 auto. I don't make a habit of using that ammo in them but have tried it out of curiosity in all 3.

[reteach]

Here's what I think I understand about the .32's:

The .32 S&W and .32 S&W Long were designed when black powder was still being used in cartridge ammo. The revolvers were made to deal with relatively low pressures developed by those cartridges.
The .32 ACP was designed for use with smokeless powder, as well as use in a semi-auto pistol, so for both reasons could be loaded to higher pressures. I do not know why Browning designed the cartridge with a small ("semi") rim, but it's there. The small rim means that you can load the cartridge into a revolver designed for .32 S&W or .32 S&W Long, but the higher pressure of the .32 ACP might damage the revolver. Also, most of the .32 S&W and S&W Longs are double actions, and there might be trouble ejecting the spent ACP brass.
The .32 H&R Mag and .327 Fed Mag are designed for much higher pressures than .32 ACP, so it's safer from that standpoint to shoot .32 ACP in one of those revolvers. There is still the issue of ejecting spent brass, but in a single action revolver, that is usually not a problem. The remaining problem is that in some revolvers the semi-rimmed .32 ACP cartridge might seat too deeply in the chamber, so the firing pin doesn't reach the primer cap.
In addition to pressures, there is of course the overall length of the cartridge to consider. For example, you cannot load an H&R Mag into a S&W Long because then cartridge is too long.
There are also some differences in typical bullet weight. .32 ACP bullets typically range between 60 and 75 grains. The revolver loads typically have heavier bullets, between 80 and 130 grains.
My own experience shooting .32 ACP in my .327 Fed Mag revolver is that it works great and is a lot of fun. The sound and recoil are greatly reduced, the ammo is accurate, and I have had no problems with loading, firing and ejecting.
That's not all there is to know, but maybe it will get you started toward the answer you need.

[FlyFish]

32 acp has a rim. its smaller than a typical revolver round but it is there. Thats why this debate can be confusing. A 32 H&R and a 327 federal revolver can chamber and sometimes shoot 32 auto. You should not attempt that in a 32 long or short firearm.

I don't know why some firearms wont successfully fire a 32 auto all the time? Not even sure if that is accurate. I have 3 revolvers in 327 federal and all are 100% reliable with 32 auto. I don't make a habit of using that ammo in them but have tried it out of curiosity in all 3.

Exactly - the .32 ACP is one of a very small number of cartridges known as "semi-rimmed". The rim diameter is larger than the base of the case, but not so much larger as a rimmed cartridge. Apparently the rim diameter of the .32 ACP is just large enough to allow it to headspace in your .327 Federal revolver. SAAMI max pressure for the .32 ACP exceeds the .32 Long or Short, so should not be fired in a firearm chambered for those cartridges.

[Jim Watson]

The semi rim of the .32 ACP is smaller and thinner than the rim on a real .32 revolver cartridge. It will hold headspace and shoot from SOME revolvers, not all. Higher pressure and narrow rim can give poor extraction.

[T. O'Heir]

The .32 S&W and .32 S&W Long(aka Colt New Police) aren't the only .32 cal. cartridges. There were lots of revolvers made in .32-20 Win too. There was a .32 Long Colt and .32-44 S&W, as well. The .32 H&R Mag and .327 Federal Mag are the new kids. Nowhere near the number of firearms chambered in either as there are the older cartridges.
http://stevespages.com/jpg/cd3220winchester.jpg
As mentioned, most pistol cartridges are rimless(the .32 ACP is considered as such despite the semi-rim.) and revolver cartridges are rimmed. Think .45 ACP and .45 Colt.

[SIGSHR]

Some revolvers were chambered in 32-20, a tapered cartridge.

[burrhead]

I know the 32 ACP has a semi rim. So what. The point is I was trying to keep it simple.

The 32 ACP SAMMI pressure in 20,000 PSI and the 32 S&W is 13,000 more or less. 32 long 14,000 +. They're NOT interchangeable. I knew I'd get nitpicked but so it goes.

[kozak6]

.32 acp is a somewhat available chambering generally found in mouse guns. Walmart might carry it. You probably aren't talking about .32 NAA. Nobody is.

.32 revolver cartridges are almost all screwball antique calibers you will have to order online, and most of them are fairly low powered. .32 H&R and .327 mag are a little more modern, but you will still probably have to order them online.

[In The Ten Ring]

.32-20 fan here although I've never held the cartridge! At some point I'd like to find a nice pre Model 10 Smith and Wesson Hand Ejector in that caliber.

[Mike Irwin]

".32-20 fan here although I've never held the cartridge! At some point I'd like to find a nice pre Model 10 Smith and Wesson Hand Ejector in that caliber."

I have a S&W M&P and a Colt Police Positive Special, both chambered in .32-20. They are a LOT of fun to shoot.

[darkgael]

There is also the .32 short Colt, now pretty much obsolete though ammo can still be found. It will not chamber in guns made for the .32 S&Ws.

[Mike Irwin]

Here's a list of the most common .32 revolver rounds you'll encounter...

.32 S&W - Once hugely popular because of the small handguns that chambered it starting in the 1870s. Obsolete, but ammunition is still manufactured.

.32 S&W Long - A lengthened version of the .32 S&W. Also once very popular. Still fairly commonly found, chambered in revolvers until fairly recently. Ammo still commonly available. Also chambered in some high-end European semi-auto target pistols.

.32 Short and Long Colt - Competitors to S&W's two rounds. NOT interchangeable with the S&W rounds. Not nearly as popular, and obsolete for a long time, although you'll still find Short Colt ammo.

.32 H&R Magnum - A lengthened, more powerful version of the .32 Long. Never particularly popular, but still encountered.

.327 Federal - Longer than the H&R and more powerful. Designed to give a 6 shot compact revolver with power approaching the .357 Magnum. Neat concept, but appears to be dying.

.32-20 - Originally a Winchester rifle round, became a VERY popular Colt & S&W revolver round. Only handgun I know that still chambers it is the T/C single shot.

There were some other .32 rounds manufactured/chambered in revolvers over the years, such as the S&W .32-44 target and the .32 Merwin & Hulbert, but they are LONG obsolete, guns are not commonly encountered, and the ammo is really in the collectors' realm.

There's also the .320 Revolver, designed in Britain, and which served as the inspiration for the .32 Short Colt. There were a lot of European revolvers chambered for this cartridge, so runs are occasionally produced in Europe and South America.

[carguychris]

Originally Posted by Mike Irwin

.32 S&W Long - A lengthened version of the .32 S&W.

This cartridge is also known as .32 Colt New Police, which was simply an alternate name concocted by Colt so that they wouldn't have to mark their revolvers with the name of their arch rival. Ammo has not been marketed under this name for generations, but you'll encounter it once in a while on old Colt small-frame revolvers.

Somewhat confusingly, .32 Colt New Police and .32 Short/Long Colt are NOT cross-compatible, as the New Police is based on the S&W cartridge family!

Originally Posted by Mike Irwin

.32-20 - Originally a Winchester rifle round, became a VERY popular Colt & S&W revolver round. Only handgun I know that still chambers it is the T/C single shot.

This round is also sometimes called .32 Winchester or .32 WCF (Winchester Center Fire), notably on older S&W revolvers and clones chambered for it. As with .32 Colt NP, you'll generally only see these names on guns, and not on recently-made ammo.

This is NOT the same cartridge as .32 Winchester Special, which is a much larger, more powerful, and totally incompatible rifle round derived from the .30-30 Winchester.

[Jim Watson]

This cartridge is also known as .32 Colt New Police, which was simply an alternate name concocted by Colt so that they wouldn't have to mark their revolvers with the name of their arch rival.

The Colt branded ammo, .32 NP/PP, .38 NP/PP, and .38 Colt Special also had the deadly flat pointed bullet. Hatcher Relative Stopping Power gives flat pointed bullets a bonus of 5% over roundnose.

[TruthTellers]

Originally Posted by Mike Irwin

Here's a list of the most common .32 revolver rounds you'll encounter...

.32 S&W - Once hugely popular because of the small handguns that chambered it starting in the 1870s. Obsolete, but ammunition is still manufactured.

.32 S&W Long - A lengthened version of the .32 S&W. Also once very popular. Still fairly commonly found, chambered in revolvers until fairly recently. Ammo still commonly available. Also chambered in some high-end European semi-auto target pistols.

.32 Short and Long Colt - Competitors to S&W's two rounds. NOT interchangeable with the S&W rounds. Not nearly as popular, and obsolete for a long time, although you'll still find Short Colt ammo.

.32 H&R Magnum - A lengthened, more powerful version of the .32 Long. Never particularly popular, but still encountered.

.327 Federal - Longer than the H&R and more powerful. Designed to give a 6 shot compact revolver with power approaching the .357 Magnum. Neat concept, but appears to be dying.

.32-20 - Originally a Winchester rifle round, became a VERY popular Colt & S&W revolver round. Only handgun I know that still chambers it is the T/C single shot.

There were some other .32 rounds manufactured/chambered in revolvers over the years, such as the S&W .32-44 target and the .32 Merwin & Hulbert, but they are LONG obsolete, guns are not commonly encountered, and the ammo is really in the collectors' realm.

There's also the .320 Revolver, designed in Britain, and which served as the inspiration for the .32 Short Colt. There were a lot of European revolvers chambered for this cartridge, so runs are occasionally produced in Europe and South America.

Good list you compiled there, but you forgot two... .32 rimfire Short and Long. Yes, they're in the collector's category now, but there are a lot of antique revolvers and single shot rifles out there chambered for .32 rimfire.

Also, I wouldn't say the .327 concept is dying, it got the carpet pulled out from under it for 8 years when it first debuted. It's come back pretty well.

[Sevens]

Of course we could argue definitions of the terms we use (we do that a lot around here... it is fun to do) but the .327 Federal does not "appear to be dying", quite the contrary. It doesn't have a long history but in that history, it's easily as ALIVE as it ever has been since it's inception.

It a definitely a niche cartridge, like other loved niche cartridges, and amongst a collection of modern niche cartridges, it is more alive and more active than most.

We'd probably argue that factory ammo offerings and currently produced gun models would be solid evidence of that, and in those areas, .327 Federal beats out many... including .25 ACP, .32 H&R, .41 Magnum, .44 Special, .30 Carbine, .454 Casull... maybe .357 Sig and/or .38 Super also?

[Mike38]

Benelli MP95E semi auto chambered in .32 Wadcutter (.32 S&W Long) Loaded to around 680fps, recoil about the same as a HV .22LR.

[Mike Irwin]

I didn't forget the .32 Rimfires... I left them off the list intentionally for several reasons...

First, ammunition is virtually unobtainable today in shootable quantities. The last manufacturing run I know of was made by CBC in Brazil for Navy Arms.

Second, there hasn't been a handgun chambered for one of the .32 rimfires since before the Great Depression, and likely not since before World War I.

Third, to the best of my knowledge, no modern (double action, swing out cylinder) revolver was ever chambered in .32 rimfire. The closest I can think of are the solid frame H&R Bulldogs.

I put the .32 rimfires in the same class as the .32-44 and .32 M&H centerfire cartridges... Neat, but obsolete as all hell.


"but the .327 Federal does not "appear to be dying"

Yeah, probably not dying. I thought Taurus had dropped production of the .327, and I just discovered that Henry is rolling out lever actions chambered for it.

[tallball]

Thank you Mike Irwin. You posted two excellent responses that covered pretty much everything.

I am a big 32 fan and own handguns chambered in all of the more popular 32 rounds. They are perfect for someone who physically can't use a 38 or 9mm or 380 for SD, and incorrectly believe they have to resort to 22 or 25.

[Mike Irwin]

Oh hell yeah, tallball, I LOVES me some .32!

As a class of cartridges, they are just so... polite... when you pull the trigger.

Right now in my collection I have...

CZ 70 in .32 ACP. That's my only semi-auto .32, but I really want some more...

In revolvers I have...

S&W Regulation Police in .32 Long. That was my first .32 revolver, and it's what sold me on the caliber.

A snub Model 30 in .32 Long. Not really all that useful, but when I saw it I just had to have it.

A Colt Police Positive in .32 New Police (.32 S&W Long). Pure impulse buy, but fun to shoot.

An S&W M&P in .32-20.

A Colt Police Positive Special in .32-20.

I really really really want to get a Marlin or Winchester lever rifle in .32-20 to go with the S&W and the Colt. I don't know why, because I live in metro Washington, DC, and the chances to shoot rifles are few and far between...


A very close friend of mine has something that I desperately covet, as well. A few years ago on his way to visit family, he stopped into a gunstore near Roanoke, Virginia, and chance upon a unicorn...

A 4" S&W Model 16 in .32 Long. It had some condition issues (looked as if it had been dropped on concrete and freckled), but overall in good condition and very good mechanical condition.

He wasn't quite sure what he was looking at, but he knew it was very special, so he grabbed it...

$500 out the door.

[tallball]

Mike, for 32acp you should really outta have a Colt 1903. They are a joy to shoot. I was lucky enough to find one that had been refinished and given new grips... so no one wanted to pay money for it. It was something like $330. The sights are tiny and it is a minor PITA to field strip, but it barely even twitches when you squeeze the trigger and shoots just where you aimed it.

And if you ever run across the elusive Beretta Model 100, it is more-or-less PPK sized, but single action. It has a 6" barrel and nice big adjustable sights. Mine is accurate like a 22.

My PPK-sized FEG is nice, too.

I have some others, but those are my favs. Keep your eyes open; I bet you can find something nice.

[tallball]

Just kinda rambling... while I do my morning breathing treatment. Then I will "shaur", as my Kentuckian wife calls it, and head over to see the gun show with her dad...

32acp can be kinda snappy, especially in small alloy pistols. 32 S&W long is gentle like a sweet, sweet lady. My FiL reloads it. I shoot a lot of 32 S&W long. 32 H&R magnum is mild and, to my understanding, a decent SD cartridge. 327 magnum gets back to the kinda snappy category.

I only shot 32 S&W short once. A friend found some in his garage that had belonged to his dad. He gave them to me, saying, "Maybe you'll get a 32 revolver one day." One day I DID get a 32 revolver, an old S&W Hand Ejector with rough finish that no one wanted ($125). I shot it a few times with S&W long, then remembered the old shorts that my friend had given me. I took them to the range on my next trip. All of them went "BANG!", but it was more like "bang". I even started to have the strange optical illusion that I could see the bullet as it limped along to the target. It turned out not to be an illusion. As I shot the last cylinder, the RSO and I both noticed that the last two rounds actually bounced off of the wooden backboard and ricocheted back towards me. He suggested that maybe I shouldn't shoot any more of those particular rounds, and I cheerfully concurred.

The old Hand Ejector has a rough trigger and barely any sights. I got an SP101 in 327 magnum, but the trigger is stiff, so it's not my favorite. My Single Six in 32 H&R, on the other hand, is lots of fun to shoot. It has a 6" barrel and adjustable sights. If I'd had it when I was a young un, I would have eaten even more possums and 'coons than I already did. That thing is dead-on accurate.

My Kentuckian wife, though a woman of considerable stature (6'4"), has messed up wrists. In the rare occurrence that I am out of town, I leave the Charter Arms Undercoverette in 32 H&R loaded for her. The recoil is squat. It's a nice easy snubby. She could use it to put someone out of their misery after her gigantic ferocious dogs were done mauling them (Ain't they so cute!).

I am pretty sure those are all of my 32 revolvers. Those and my 1903 Colt were instrumental in teaching my daughter to shoot when she was eight or nine. Now she is 13 and 6'2", so she shoots whatever she has a hankering for at the moment.