P32 rimlock

this sliding action doesn't occur with full length rounds such as rn fmj.
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It can and does occur with fmj ammo. All depends on the magazine. Some work well while other allow too much movement, even with round nose bullets such as 71 gr fmj.
 
For several years, I carried a JHP round in the pipe and top round of my KelTec P-32 magaine. The rest of the rounds were FMJ rounds. Several years ago, I finally bought two rim lock eliminator kits from KelTec which consist of a flat shim that rides at the rear of the magazine. It rides in a notch of the replacement follower they send you and is held in place at the bottom by a modified base plate catch system. These really work however, I still had one brand of JHP .32 ammo that would occasionally rim lock.

With these kits installed, you cannot load a FMJ round into the magazine.

I thought that my Sig 230 in .32 ACP caliber and my Beretta Model 70 32 ACP would not rim lock since they were straight blow back systems unlike the Browning, tilt barrel locking system of the KelTec P-32. (I thought they would have enough inertia that they would over ride the rim lock when it occurred.) However, they both experienced rim lock with some HP rounds.

A question was raised why rim lock is not experienced in a 22 LR. It is because the rounds are all the same length (about). I think if you loaded some 22 longs in a magazine of a 22 LR pistol, you could get it to rim lock (if the gun would even function).

Neat topic, and yes, rim lock is real.

Trooper Joe
 
Boy have I led a sheltered life, I have twelve or fourteen .32 auto pistols and never experienced nor even heard of " rim lock" as all my pistols seem to feed everything I stuff in. I use only ball ammo with the exception of 500 rounds of Winchester white box, again not knowing it is prone to malfunction I have shot a bunch without incident. What a sheltered life I lead:) my Keltec is a P 380 that I use as a truck pistol loaded with ball, just my choice of ammo in autos as I find it functions 100% in all my pistols (and costs less also).
 
I've never experienced rim lock in my CZ 83 chambered in .32 Auto, and it uses a 15-round magazine.

Rim lock is primarily a function of the semi-rimmed design of the case. In the instance of the .32 Auto, in 1899 the first of Browning's ACP designs, the channel between the base of the cartridge and the semi-rim was just the right width that the rim can fit in tightly and lock up -- a flawed design. It's my understanding that some manufacturers (I can't recall which ones) have redesigned the channel to slope more gently out to the cartridge base, thus effectively widening the channel and preventing rim-lock.

Browning designed six autoloading pistol cartridges from 1899 through 1908. Four of these were semi-rimmed. Two of these -- the .38 Auto and the 9 Browning Long -- are essentially extinct; I don't know if they were plagued by rim-lock or were simply out-competed by the 9 Luger (a rimless round). The two extant rimless cartridges are the .32 Auto and .25 Auto, but I've never heard of the latter experiencing rim-lock. The .25 Auto was Browning's penultimate auto pistol cartridge design (in 1905), and I think he had learned by then to have the channel between semi-rim and base wider than the thickness of the semi-rim.

The two most successful Browning pistol cartridge designs -- the .45 Auto and the .380 Auto -- are rimless. They were generated in 1904 and 1908, respectively, and were likely influenced by lessons learned from his earlier designs, and perhaps from the performance of the rimless 9 Luger, which appeared in 1901.

In regard to the FBI minimum bare gel penetration criterion of 12 inches, one would be wise to heed it. As far as I know, in .32 Auto one can have either adequate penetration or expansion, but not both. Per the handgun terminal ballistics experts expansion without adequate penetration is a dangerous combination for the shooter.

As far as ridiculing the FBI criterion (I try to abide by the original IWBA criterion of 12.5 inches minimum), I assume such jabs are made in an absence of knowledge; such as:
  • X inches of penetration in calibrated gel does not translate to X inches of penetration in a human body; count on the latter being less, perhaps far less; calibrated gel is a soft-tissue simulant, but humans contain hard tissues, too.
  • The IWBA ammo specs -- eg, minimum average bare gel penetration of 12.5 inches with a standard deviation no more than 1.0 inch -- are intended to ensure that the overwhelming majority of rounds will penetrate the gel at least 11 inches, which should be enough for most rounds to penetrate a human body deep enough to reach vital organs allowing for complicating variables such as larger body sizes, intervening obstructions (eg, outstretched arms), and nonideal shot angles (eg, a side shot rather than a frontal shot).
I think Urey Patrick's FBI report on handgun wounding factors acknowledges that 8 inches of gel penetration is often enough to make a round effective, but the IWBA and FBI weren't/aren't interested in being effective often, but rather being effective the overwheming majority of the time. After all, when 75% of your shots miss, the few that are likely to hit need to have the potential of counting, and if they don't reach vital organs they can't be relied upon to count.

I'm a big guy who wears an XXL shirt. My chest is about 8 inches deep. A bullet striking my unobstructed sternum that penetrates only 4 inches will almost certainly destroy vital tissues. But, those vital tissues are surrounded by hard bone and covered by tough skin, and if I'm ever being shot at I hope I don't offer my assailant an unobstructed frontal shot.

Ignore FBI handgun round performance standards at your own risk and at the risk to your loved ones.
 
It's interesting that one of the most popular autopistol cartridges of all time is "flawed!" :rolleyes:
The .38 auto became the Super .38 automatic cartridge-which is still in use today.
The magical "FBI penetration tests" were the FBI covering their ass. This vaunted document changed nothing (except perceived "experts")opinions.
 
PSP,

My CZ 83 .32 was made in 2012, and my mags have the indented rear wall like the one on the left in your photo.

So the indentation is supposed to function as an anti-rim-lock modification? I've never shot JHPs from it and never will. And, the ammo I've used so far seems to have case dimensions that are not conducive to rim-lock.
 
It's interesting that one of the most popular autopistol cartridges of all time is "flawed!"

The .38 auto became the Super .38 automatic cartridge-which is still in use today.
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The .38 Super +P is regarded by most to be a separate caliber from .38 Auto, although they do use the same semi-rimmed case dimensions. Based on ammo observed on gunshop shelves and the few pistols made for the round, I doubt it's fair to characterize the .38 Super +P as "one of the most popular autopistol cartridges of all time." It was popular among police for a time until the .357 Magnum came along, then they dropped it like a hot potato for the more reliable revolver platform. Today the cartridge seems to be a niche gun for combat gamers who don't want to shoot a .45 Auto. Perhaps there is a sizeable community of .38 Super +P handloaders of which I'm unaware? If so, they don't seem to be buying many pistols. Glock hasn't bothered to make a gun that will shoot it have they?

The magical "FBI penetration tests" were the FBI covering their ass. This vaunted document changed nothing (except perceived "experts") opinions.
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If I ever find myself in a gunfight, I hope and pray my opponent has a Glock loaded with Glaser Safety Slugs.

May I ask what your criteria for selection of a self-defense cartridge are?
 
^Again, judging by the amount of ammo on shelves, by how few .32 Auto pistols are sold, I wouldn't consider it a popular caliber today.
 
Limnophile said;
My CZ 83 .32 was made in 2012, and my mags have the indented rear wall like the one on the left in your photo.
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Had you owned the original mag, no indent, you would be very familiar with the joys of rimlock, especially with American ammo. Some European ammo would feed but also occasionally gave problems too. CZ changed the mag tube and fixed the problem.

FWIW, the CZ83 in .32 is about the most fun a human can have with a firearm, when it works that is. ;)
 
Had you owned the original mag, no indent, you would be very familiar with the joys of rimlock, especially with American ammo. Some European ammo would feed but also occasionally gave problems too. CZ changed the mag tube and fixed the problem.
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I like to feed it Euro ammo -- hotter and a bit bigger bullet.

Do you know you what year the mag design changed?

FWIW, the CZ83 in .32 is about the most fun a human can have with a firearm, when it works that is.
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There are plenty of folks admitting they used to own one who regret selling it.
 
^My .32 mags are readily identified as different from my .380/9 Makarov mags (which are interchangeable). Before the design change I was there an obvious difference, or did one have to compare followers and distances between feed lips?
 
FBI says 12 inches Their more interested in having enough power to shoot thru ,walls ,car bodies ,windshields, and other barriers . Than how good the HP act on humans .

Now Border Patrol in most gunfights of Federal agencies Says that 10 inches is fine . Also their talking about service calibers not 32 acp or 380.

They could care less about those. 25 auto ball will penetrate 16" of the jell.
So it more than meets the FBI requirement, Since seems most have trouble qualifying with the present caliber and want to return to 9mm . Maybe should just issue 25 auto low recoil meets the 12" plus and easy to conceal.
I am sure Beretta would love to out fit them. :rolleyes:
 
Lone Wolf makes a Glock 20 barrel in 38 super
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But, as I accurately pointed put, Glock has never seen fit to produce a pistol in .38 Super +P, which is a testament to my claim that the caliber is not particularly popular. I misunderstood that Bill was referring to the .32 Auto; but, Glock's failure to produce a pistol chambered for it refutes his claim pertaining to that caliber in recent times, although he is correct if the era in question is the first half of the 20th century.
 
People say rim lock occurs with .32 ACP and I have no reason to doubt their veracity, they say it happens, then it happens , period. However in my own experience, I have taken four different magazines { four different guns, A Kel-Tec-P32, a NAA Guardian , a Colt 1903 and a CZ 70 } and deliberately tried to incur this effect and was unable to do so by loading the magazines in the normal manner. Perhaps by using something such as a small screwdriver and forcing the top cartridge down and placing the next cartridge over the rim of the lower cartridge, however I was not even able to duplicate that . So, perhaps I'm loading my magazines wrong, not being able to incur rim lock, don't know. Prior to the influx of the new small .32's I had never heard of rim lock. I have never heard of it happening with .25 ACP?
 
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FBI says 12 inches Their more interested in having enough power to shoot thru ,walls ,car bodies ,windshields, and other barriers . Than how good the HP act on humans .
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There is much misunderstood about FBI handgun terminal ballistics testing. According to the late George Box, Professor of Statistics at the University of Wisconsin: "All models are wrong, but some are useful." Experts in terminal ballistics -- eg, trauma surgeons, medical examiners -- have determined that calibrated 10% ballistic gelatin is a useful model for simulating soft human tissue. Regarding shooting through various barriers, the FBI has separate tests for those, so we can dismiss that as irrelevant to this discussion and, generally, to most discussions of civilian self defense.

An observed penetration of X inches in gel does not guarantee the same X inches of penetration in a human body. In fact, X inches in gel, a soft-tissue simulant, is assumed to translate into much less that X inches in the human body, which has a considerable amount of hard tissue (bones), especially in locations that protect vital tissues.

Take the '86 Miami FBI shootout, which was the impetus for bringing military terminal ballistics science to law enforcement cartridge selection and design. The bank robber who ended up killing two agents and wounding several others was hit early on by an FBI 9 Luger 115-gr Silvertip. It was a side shot that struck him in the upper arm and into his thoracic cavity. While it destroyed enough vital lung tissue to be unsurviveable, it lodged about 1 inch short of his heart. If his heart would have been penetrated, he would have likely been stopped, if not immediately, within seconds. Instead, the fight continued on for minutes resulting in two agents dying and five others being wounded.

The 9 Luger 115-gr Silvertip had a bare-gel penetration of about 10 inches at the time. The International Wound Ballistics Association -- corrolating what was seen in battlefield hospitals, in city ERs, and in autopsies against what was seen in standardized terminal ballistics testing -- determined that a minimum of 12.5 inches of penetration in bare gel, on average, was needed to ensure a reasonably high likelihood of a given round penetrating the human body deep enough -- taking variables such as body size, the potential for obstructing limbs, and less-than-ideal shot angle into account -- to reach vital tissues. For some reason the FBI shortened this to 12.0 inches; until I learn the reason why, I'll stick with the IWBA criterion.

The FBI's 1987 report on handgun wounding factors acknowledges that 8 inches of gel penetration is usually enough to get the job done, but winners in life-and-death encounters don't plan for the average or to be just good enough.

If you read the notes in the IWBA's ammunition specification, the recommended minimum average penetration of 12.5 inches comvined with an attainable standard deviation of 1.0 inch, based on a sample size of 10 shots, results in a round in which one can be 95% confident that 90% will penetrate at least 10.8 inches of bare gel (if my recollection is accurate).

Now Border Patrol in most gunfights of Federal agencies Says that 10 inches is fine . Also their talking about service calibers not 32 acp or 380.
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With the IWBA ammo spec and a tolerance bound calculator, each user can do his own testing and risk assessment and make his own choices. I suspect that the FBI lowered its minimum penetration criterion from the IWBA's 12.5 inches to 12.0 inches because favorite cartridges may not have been making 12.5 inches. I imagine that the Border Patrol has similar unsound reasons justifying their position, a citation for which would be appreciated. If you look at premium LE JHP ammo manufacturers, they seem to settle for 11.0-in penetration or less through bare gel, but they must balance their designs to meet or approach the several other penetration criteria the FBI testing protocol has.

While .32 Auto and .380 Auto are not currently service calibers in the US, they have been service calibers in the relatively recent past here and in several European countries. Today it is not uncommon for LEOs to carry a .380 Auto as a backup gun.

They could care less about those. 25 auto ball will penetrate 16" of the jell.
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While the FBI places most importance on penetration, that is not the only criterion they use. Their announcement last year for the first time clearly made recoil a criterion, because recoil effects shooting speed, accuracy, and precision. It's clear that capacity is now also regarded as important.

Perhaps the second most important criterion, at least in 1987, was bullet diameter and resulting wound volume. Urey Patrick's FBI report clearly gives the nod to the larger bullet, given equal penetration. Last year's FBI announcement withdraws from this position somewhat, as the justify going back to the 9 Luger in part by noting that trauma surgeons and medical examiners cannot determine the difference between .355-caliber and .451-caliber bullet wounds from the wound channel, entry, and exit wounds alone -- the bullet must be recovered for them to be sure. This is undoubtedly an artifact of societal mores not allowing experiments involving controlled shooting of people. Even if such an experiment was allowed, the dirty secret of statistical hypothesis testing is that with a large enough sample size you are guaranteed of observing a significant difference. In this example I would put my money on the .45 Auto being more effective, on a per-hit basis, than the 9 Luger. However, the fact that trauma surgeons can't tell the difference without recovering the bullet tells me the difference can't be that big.

When other factors, such as recoil and capacity, are factored in, I suspect that the optimal caliber for self defense and general law enforcement and military uses is some type of 9mm. Long before the availability of today's sophisticated 9mm JHPs, the handgun and cartridge manufacturing community seems to have focused on production of systems nominally chambered in something close to 9mm, as measured by the number of 9mm calibers that do exist or have existed relative to 10mm, 8mm, or any other nominal caliber.

So it more than meets the FBI requirement, Since seems most have trouble qualifying with the present caliber and want to return to 9mm . Maybe should just issue 25 auto low recoil meets the 12" plus and easy to conceal.
I am sure Beretta would love to out fit them.
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I don't think Beretta is making anything chambered in .25 Auto these days.

If Glock were to modify a Glock 19 and chamber it to shoot .25 Auto, I would expect it theoretically to shoot faster and with better accuracy and precision -- maybe. On the other hand, smaller powder charges are going to be harder to control from cartridge to cartridge. For example, a powder charge good to +/-0.1 gr may be just fine in a large charge pushing a 230-gr bullet, but might be unacceptably large variance in a small charge pushing a 50-gr bullet.

I suspect there is a reason why the few .25 Autos we see are pocket guns intended for short-distance work and not full-size autos. The US Army Pistol Team shoots customized M9s, most of which can fire a 10-shot groups from a machine rest that are less than 1.5 inches in diameter at 50 yd. I somehow doubt that could be done with an M9 modified to shoot .25 Auto.

At some point there is an optimum caliber or small range of calibers. For a general service duty handgun, that's nominally somewhere between 9mm and 12mm, and almost certainly closer to 9mm if expanding bullets are allowed.

For backup or deep concealment work, .25 Auto with FMJs is a viable option. James Bond's first pistol was a Baby Browning chambered in .25 Auto. That is because his creator, Ian Fleming, was issued that sidearm when he was commissioned in the Royal Navy during WWII, leaving him with the impression that it was a valid caliber for use in social settings. Early fans who were more savvy objected, and Bond was issued a Walther PPK chambered in .32 Auto for general carry. If mouse gun calibers kept the UK safe for monarchy, then they must have some utility.
 
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