.25 ACP REVOLVER?

[grayelky]

I have been kicking something around for a little while, and the "We want a 32 ACP" thread has prompted me to share it: Is a .25 ACP revolver feasible? A good idea? I thought perhaps with a more modern loading and a good, well designed HP bullet, the .25 ACP may become useful as a self-defense weapon. It could be adapted to the mini revolver design with relative ease by changing the shape of the firing pin on the hammer nose. We would then have a more reliable centerfire cartridge for self defense. So, yes, I think it is "feasible". I believe it could be based on the mag frame mini, and with just a slight mod or 2 would would work just fine. We would also pick up the reliability of a centerfire vs a rimfire. Then I looked at ballistic tables.

   

   http://www.hornady.com/ballistics-resource/ballistic-chart">http://www.hornady.com/ballistics-resource/ballistic-chart

   

   In .22 mag, the Hornady 45 gr FTX leaves a 1 7/8 barrel at 1000 FPS, and has 100 ft/lb of muzzle energy. The Hornady .25 auto 35 gr XTP leaves a 2" barrel at 900 FPS and has 63 ft/lb of muzzle energy. At 100 yards, the .22 mag has 12 ft/lbs more energy than the .25 ACP has at the muzzle. I strongly suspect the penetration would be much less than the .22 mag. Based on the ballistics table, a .25 ACP revolver would gain absolutely nothing othter than centerfire reliability. This tells me I do not need, nor want a .25 ACP. It can do nothing .22 mag does not do better, even useing a more modern loading for the .25 ACP. So, I looked at the .32 ACP in the same Hornady ballistic table.

   

   Again, the .22 mag, 45 gr. FTX bullet, 2" barrel at the muzzle: 1000FPS, 100 ft/lb.

   

   The .32 ACP with the 60 gr. XTP bullet leaves the muzzle at 1000 FPS, and has 133 ft/lb of muzzle energy. The .32 ACP bullet is 25% heavier, and has the same muzzle velocity and has 1/3 more muzzle energy. BUT, it does it from a 4" barrel, not a 2" barrel. If we were to reduce the .32 ACP to a 2" barrel, and thus "level the playing field", the .32 may be as anemic as the 25 ACP. From a ballistics perspective, it does seem the .22 mag is the best "bang for the buck" to be had in a small, carry gun.

   

   By no means do I mean to infer my conclusions are correct for everyone else. If you want something, that is sufficient. You need no other reason for its existence. This may shed some light on why NAA has not pursued the .32 ACP any further. Would I still buy a .32 ACP if NAA built one? Likely. I am buying 2 Sidewinders, and currently have no plans to carry one.

[airplinker]

You make good points Gray. I would still choose the slightly better ignition, the larger frontal mass, and the bigger hollowpoint at spitting distances.

[heyjoe]

the following information is taken from ballistics by the inch for 22 magnum, 25 acp and 32 acp, all froma 2 inch barrel. the  muzzle energy in foot pounds is based on the formula using weight and velocity of the bullet found on georgia arms website.

   

   22 long rifle

   CCI 40 CPHP (copper plated hollow point) Velocitor- weight 40 grains, velocity 882 feet per second = 69.1 fpe (foot pounds of energy) muzzle energy

   

   Winchester Super x RN(round nose)- weight 40 grains, velocity 862 fps= 66 fpe

   

   

   25acp

   

   Winchester expanding point- weight 45 grains, velocity 816 fps = 66.6 fpe

   

   

   32 acp

   

   Corbon HP (hollow point)- weight 60 grains, velocity 944 fps = 131.7 fpe

   

   Federal Hydra Shok HP- weight 65 grains, velocity 805 fps= 93.6 fpe

   

   Winchester FMJ (full metal Jacket)- weight 71 grains, velocity 782 fps= 96.4 fpe

   

   According to these numbers all from 2" barrels, there is no difference between the 22 long rifle and the 25 acp in muzzle energy. the 32 acp has a definite advantage over the 22 long rifle in muzzle energy of 50% for the hydra shok and winchester fmj and double the muzzle energy of the 22 long rifle for the corbon .32acp.

   Grayelky's numbers for the hornady ftx of 100 fpe out of the 1 7/8" barrel would put it slightly above par with the hydra shok and fullmetal jacket 32 acp but still 30% less than the corbon 32 acp. His point is well taken by me however that there isnt that much difference anymore between the 32 acp and the 22 magnum out of 2" barrels with the improved 22 magnum ammo.

   

   the 32 acp still has the advantage of making a bigger hole .309 compared to .224 for the 22 magnum.

[Uncle_Lee]

I will take two Hoglegs in either 25 or 32 acp.

   

   

   

   

   

   

   

   

   

   The above post is just the desires and wishes of the poster only.

   It is not meant to mislead or influence others.

[Dinadan]

I decided to dredge this thread up from the dead because the forum has been a little boring lately. I wanted to make the point that since the 22 mag is a longer cartridge than either the 25 ACP or the 32 ACP, if we had frame and cylinder made just for ACP, we could have an extra 1/2 inch of barrel without lengthening the gun. A gun the length of the Black Widow would have a 2 1/2 inch barrel (more or less) instead of a 2 inch barrel. That would shift the ballistics in favor of the ACP. Another point: I do not know how the ACP ballistics were calculated, but it is my understanding that with a revolver the cylinder is not counted as part of the barrel length, where as with an auto the chamber is included in the barrel length. In that case the barrel of a 2 inch ACP auto would actually be comparable to a 1 inch revolver barrel, which would mean that if you put the same ACP round into a revolver with a 2 inch barrel it should perform a lot better. Grey, Heyjoe, what do you think about the ACP ballistics out of the 2 inch barrels: are they really 2 inches or are they 1 inch of chamber behind 1 inch of barrel?

[heyjoe]

its an interesting observation and one with some validity. i dont have a chronograph myself, but i know people who own the smith and wesson 9mm revolver which uses a .38 cylinder cut for 9mm and 1 7/8" barrel and they are actually getting slightly better velocity than with the glock 26 with the same ammo. the glock has a barrel length of 3.43 inches. So the extra length of the .38 cylinder helps the 9mm to obtain higher velocity no doubt.

[FrRichard]

heyjoe
The Velocitor is a .22LR round, not a .22mag round.  It is one of the best .22LR rounds, but it is not comparable to a magnum round.

[grayelky]

dinadan does make some valid points. The barrel length of an auto includes the chamber, but the barrel of a revolver is measured from in front of the cylinder, which is the chamber. Perhaps if we  actually had a 2" barrel in front of the 25 ACP or 32 ACP, the ballistics may be better. Not having a .25 ACP here at the house, I am going to make a guess and say the overall length of a 25 ACP is right at 1/2", maybe a slightly less. The effective barrel length then would be about 1 1/2", giving the .22 mag revolver a longer barrel in which to burn powder.

With the accuracy of investment casting, maybe it would be feasible to cast the hammer with a pointed center section instead of a long skinny section. This would give the center fire ignition ability. I have no clue as to the durability of it, but I suspect it would be completely adequate.

I have looked at the small revolvers using .380, 9mm and 40 S&W ammo. My personal opinion is the frame needs to be redesigned to take advantage of the shorter overall length of the auto cartridges, as opposed to sticking them in a cylinder built for a .38 Sp. Where is the advantage of using the shorter auto cartridges if the bigger frame is used? We would have the same situation if the .25 ACP were adapted to the Mini mag frame. For my $.02 worth, why not make the frame smaller to take advantage of the shorter cartridge (either 25 or 32), thus making the revolver easier to carry, a little lighter and easier to conceal. I suspect a shorter frame and a 2" barrel would still result in close to an overall length very close to 1 5/8 barreled .22 mag.

[Dinadan]

I agree that if an ACP revolver were to be designed, it would be better to shorten the frame to fit the cartridge. For the .32, the frame would have to be changed anyway to allow for the larger diameter of the cartridge. Not sure if a .25 ACP chamber could be bored into into the .22 mag cylinder or not. I like the way the Magnum minis look with the very long cylinders, but I also like the old short cylinder revolvers. It makes for a more balanced looking gun, in my opinion, when the cylinder length to diameter is shorter than with the Magnum minis.

[RogueTS1]

Gray; just measured some Winchester 50 grain white box .25 acp I have lying around. It comes in right at 7/8" in overall length.

[heyjoe]

heyjoe
The Velocitor is a .22LR round, not a .22mag round.  It is one of the best .22LR rounds, but it is not comparable to a magnum round.

thanks, i corrected that error.

[CavScout]

<snip>
With the accuracy of investment casting, maybe it would be feasible to cast the hammer with a pointed center section instead of a long skinny section. This would give the center fire ignition ability. I have no clue as to the durability of it, but I suspect it would be completely adequate.
<snip>

I have, and have had several S&W top-break revolvers. The centerfire models have their firing pin integral to the hammer forging (i.e. - fixed). I've never had one break, nor have I noticed that as a common flaw on GunBroker "parts" gun listings.

[AZsnipe]

The problem that I see with the .32 ACP or the .25 ACP is that they are ACP.  They will need some type of "moon clip" for them to operate properly in a revolver....just like the old .45 ACP GI revolvers did.  That wouldn't be a deal breaker, but it would involve another step to loading, and another piece of hardware.  On the other hand, it is pretty easy to pre-load those full moon clips and get a quick re-load.

Snipe

[heyjoe]

you can shoot 32 acp in 32 long, 32 H&R and .327 revolvers without moon clips. 

[grayelky]

The problem that I see with the .32 ACP or the .25 ACP is that they are ACP.  They will need some type of "moon clip" for them to operate properly in a revolver....Snipe

The .45 ACP is a true rim less cartridge, as is the .25 ACP, .40 S&W and 9mm. The reason for the moon clips is to eject the empties. The case still head spaces on the case mouth, so that is not a problem. The current design for the minis (with the exception of the sidewinder) requires the cylinder to be removed to eject the empties, so ejection will not be a problem. If the SW were scaled up to .32, then it still would not be a problem. To expand on Heyjoe's comment, the .32 ACP is a semi-rimmed case. It has a slight rim, but enough to head space on, and facilitate ejection like the rimmed cartridges do.

[Uncle_Lee]

32 ACP MINI!!!!
I'll take two


25 acp mini??
I'll take two


Just about any "different" new model.
I'll take two

[louiethelump]

The 25acp is also semi rimmed.  That said, the standard mini with a center pin used as an ejector rod would work with any of them without moon clips.  The Break top or the SideWinder would work with 25acp or 32acp but would not extract the others.  (38 super is also semi-rimmed)

This was the reason some of us have promoted the 32acp.  It operates at the same pressure as the 22 magnum, and is semi rimmed.

I have a S&W 432 that I put the extended firing pin in, and it is now 100% reliable with 32acp.  It is a J frame 6 shot and is bigger than a 5 shot mini would need to be.  It extracts just fine by the way.  The 32acp is clearly an improvement over the 22 magnum, where the 25acp is not.  (save your dispute B.S. over that issue and just call it my opinion if you want, or just go do your own research on it and find out what the 22 magnum REALLY does out of a 2" barrel)  A 25acp mini in the size of the 22 short mini would be something I would buy two of. 

[Uncle_Lee]

Ditto with louie..

[keith44]

Louie,
The length of the magnum mini frame should work fine with the .32 acp (maybe even the LR frame).  I am curious how much thicker the frame, and bigger around the cylinder would need to be to accommodate the .32 acp.  While it would make a curious gun, I wonder if it would make it too thick to hide easily.  IMO the strong point of the mini is the ease of hiding them.

Just curious

[Uncle_Lee]

As for me, I wouldn't hide it (except from the wife), I would show it off.

[bill_deshivs]

The thing that .22 magnum does best is "loud"- out of handguns, anyway.
A .25 mini would be cool.

[Uncle_Lee]

I'd buy a pair of .25 acp minis.


I'd buy a pair of any NEW model minis.

[heyjoe]

Louie,
The length of the magnum mini frame should work fine with the .32 acp (maybe even the LR frame).  I am curious how much thicker the frame, and bigger around the cylinder would need to be to accommodate the .32 acp.  While it would make a curious gun, I wonder if it would make it too thick to hide easily.  IMO the strong point of the mini is the ease of hiding them.

Just curious

true Keith but a 32 acp mini would still be a very small centerfire revolver.

[heyjoe]

I also would buy both a 32 acp and 25 acp mini revolver. no surprise there.

[Dinadan]

I have a question for you experts out there. Could the existing .22 mag cylinder be bored to accomodate a .25 ACP cartridge and maintain a safe chamber wall thickness? Not much room to play with, but not much would be needed. If the existing cylinder and frame could be used, then the hammer would need to be altered, and the barrel bored slighly larger, but those are fairly small changes, or so it seems to a man who has never designed a gun.

[OV-1D]

It's obivious that a 25 , to them I hope , could be designed for a four shot with that room and have integrity . 32 would be pushing it to extremes and unwise to shoot . 

[boone123]

Dinadan'
That wouldnt leave much meat in either the cylinder or the barrel, as the minis now are.
One thing about it, if you shoot somebody with a 25ACP, his family probably won't sue you for killing him, cause you will probably only hurt him anyway. Might want to carry a knife or a brick to finish the job.
I have an old copy of a paper 9GUN WEEK) around here from maybe the 70s where a guy was shot I think 9 times, but 13 sticks in my head. Didn't know he had been hit> Bullets just made little round holes. A  25ACP might be kind of cute, but I might take my brick also.
Just me.

[Dinadan]

Boone - I am not saying that the .25 ACP is a great round. But in my post back on Nov 17 I was trying to point out that comparing .22 mag out of a revolver against .25 ACP out of an auto is misleading. Because of the different ways that auto and revolver barrels are measured, a .25 ACP out of a 2" auto  actually has only about 1" of barrel in front of the cartridge: while a .22 mag out of a 2" revolver actually has 2" of barrel in front of the cartridge. That different way of measuring barrel length makes it look like the .22 mag has more advantage than it probably would if fired from an exactly comparable gun.

[OV-1D]

Hey boone thats how I feel about all these rounds 9mm and under . Between clothes and jackets and things ( drunks ,druggies and ofcourse the insane ) plus the diameter of these small calibers most are just pissed off after getting hit because these people are not naked afterall . It really isn't like in the movies , most criminal people don't stop and drop unless a critical area is penertrated  neck , center chest , groin area , head , kill shots generally . So if one isn't Annie Oakley in a tight situation you want something that will atleast spin them around or knock them down 38,357,40 my favorite 45 . Now a 22 gatling gun would probably do it but this is only my lifes opinion , anything other that those calibers are pretty much firecrackers with the bad guys that have a real purpose . If and when I ever have to shoot I'm always visiualizing at a 300 lbs bad guy or guys with baseball bats . 

[boone123]

Dinadan'
I know what your saying, but I just don't care for 25 acp.
It goes back to each his own.
I really don't think a 25 acp revolver would sell very well.
If  I were proved wrong, great!
I think due to the low powered shell, and the cost of the ammo, a lot of people that think they would want one. with more thought , would pass, once it was laying there within reach.
Just me.

[Dinadan]

Boone and OV-ID - you might both very well be correct. And I would rather see a .32 ACP mini than a .25 ACP. But it is still fun to kick the idea around. Heck, even if we had a .44 mag mini, some folks would still hold out for a 12 guage!

[OV-1D]

Twelve gauge with double odd buck thats the ticket . Slugs are good too . I want two mini 12 gauges when they become available .

[G50AE]

Twelve gauge with double odd buck thats the ticket . Slugs are good too . I want two mini 12 gauges when they become available .

LOL, OV-1D That's funny.

heyjoe previously mentioned the Winchester .25ACP "expanding point" round.  This round has a tiny piece of bird shot placed in front of the round to ease feeding in certain .25ACP semi-autos.  It does not, act like the polymer ball in a Glaser Pow'R ball round and promote expansion.  I would be curious how effect a Pow'R ball round, if Cor-Bon were to make one, in .25ACP.

[redhawk4]

I'm late to the party here, but have often wondered my self why NAA doesn't do a Mini in 25 ACP. With the right ammo you can get 22 mag performance from a potentially more reliable centerfire round and could have a lot more compact gun, or a longer barrel because the cartridge and consequently the cylinder length could be so much less.

25 ACP is a round that has been forgotten about because of it's small size, but also because of the rumor mill of it being less powerful than 22 LR which originated with people erroneously comparing 22 LR rife ballistics against 25 ACP rather than 22 LR ballistics from short handgun barrel. A lot of people have been killed by the so called "non lethal" 25 round. I saw a documentary of a real case recently where 4 people in the same room, 3 of them Highschool football players were all murdered with a 25 ACP semi auto, non of them just got angry and attacked the shooter as is often claimed for this round.

What is a shame is that because it's become the "forgotten round" it's pricey to buy and also there seems to have been zero ammo development done. Some of the European manufacturers seem to have the best muzzle velocity, but I'm sure if someone was to revisit development with the latest powders etc. another 100 fps of muzzle velocity could easily be found.

[cfsharry]

That the .25 is less potent than the .22LR is no myth.
The best .22LR tested by BBI was the 40 gr. CCI Velocitor at 882 ft/sec and 69.1 ft/lbs of energy.  The best .25 tested was the 50 gr. Winchester at 780 ft/sec and 67.5 ft/lbs of energy. Both from a two inch barrel with no cylinder gap.
That is, to me anyway, pretty conclusive evidence that the .25 is an anemic round and, other than for a 'cool' factor, why a .25 revolver is very much un-needed.