SACM 1935A --Surprisingly Compelling

Why aren't these more popular?!

I mean, I know the ammo situation is mildly annoying (though I'll bet Starline can easily do a run of Longue/Pedersen if they cared to) but this is a seriously nice gun. Flat, thin, trim, lightweight, great trigger, and easily the most comfortable handgun I've ever held (think "Luger" only better). It also looks extremely handsome, as you'd expect of the ancestor to the SIG P210.

Very compact slide/frame arrangement due to the narrow chambering. I am usually the first to deride frame-mounted safeties as being needlessly cumbersome or out of the way, but the slide height is so short the lever is practically where a 1911-style safety lever would sit on a larger gun already. The safety is about as fool-proof as a Beretta's, also, though it does turn the wrong way (points upward for safe; gun was meant to be carried empty). The frame/slide fit is quite loose-goosey on this well-worn example, but the barrel is solidly locked to the slide in battery, with maybe five-thou of play at the muzzle end (not bad for such an old gun).

Quality 1911-style magazine, and most importantly with a similar mag-release button at the trigger guard, unlike the P210 (until recently). There is a mag-safety on the right side which prevents mags from dropping free, unfortunately (though it is not the type to hurt the trigger pull, unlike the Hi Power)

The only function issue with this one is a dry-fire firmly lodges the (spring-returned) firing pin the forward position, a good 1/4" proud of the breechface . Feels like some old gunk or maybe a raised burr in there, the barrel link is also a little stiff & needs cleaning.

The sights are, well, pre-WWII pistol sights. Nothing special, although the rear notch opening is a fairly wide & extremely sharp square shape with a wide blade surrounding it, which makes them the best of these 'vestigial' pistol sights I've yet encountered.

Seems like an extremely well thought out weapon, borrowing the best elements of its time and then some.
-Very durable safety (drum type rotates to block the firing pin & disables sear)
-Thumb-activated mag release --very forward-thinking for Europe in its day
-Modular trigger group (can be removed as a unit)
-Captive return spring/guide rod unit
-Quality sliding-stirrup trigger (trigger pivots, but transfer bar slides up at a 45deg angle)
-Ridiculously comfortable grip
-Respectably powerful cartridge, 77gr @ 1100fps, especially considering the size differential with more powerful 9mms or the recoil of smaller 380s

Things that could change;
-move safety to frame, though it may get crowded on this small a frame
-or forego manual safety for a grip-safety
-longer slide-release, as it is at thumb-tip now (sling-shot likely the intended manual of arms, though)
-ditch the magazine safety, or move the pressure point up to the feed lips so it helps push the mags out upon release, rather than holding them inside the gun
-scalloping the top edge of the bakelite grip panels so the short slide can be more easily grasped
-better sights, but they'd be worn down to these nubs after nearly a century anyways

Truly a great design that a wise company (CZ-USA, for example, as a sort of "mustang" version of a CZ75...) should totally bring back as a 32acp, or even simply as the original caliber renamed to something like "300 Badass" with a dedicated run of ammo by a manufacturer. Maybe use cut-down 30 Carbine brass, and see if the power can be amped up a little for nastier hollow-point expansion.

TCB

I think even the Borchardt had a button release; like, literally the first autopistol ever designed used a thumb-button, and everything since has been a mistake

"Buffalo Arms makes brass by turning the rims off .32 S&W Long. I have read of making it out of .30 Carbine."
I've heard that, too; my hope is I can grind a profiling tool & do the conversion fairly easy on my lathe. Knock out a few dozen & keep track of them, and it should last a while. I've heard 32acp dies work, also, which is a good excuse to start loading for the VZ61, I suppose.

"Overall my experience with French pistols has been quite positive and I would expect one of these to be no different."
They really did make some very good stuff up until the fifties, but it's usually been weird in some way that keeps it from catching on (the MAS bolt rifle lacked a safety, the MAS autoloader has the funky mag catch and bright nylon cocking knob, the PA-15 is a tank-like beast, and even the Mle 1873 revolver is a preposterous tank of a handgun), sort of like how all British designs since the Brown Bess have been ugly-lookin' (and flint lock's kinda look funny as a rule)

"Could the chamber simply be reamed to 32acp to headspace on the semi rim?"
The mags won't tolerate a semi-rim; what folks did is turn off the rim & press/solder a steel collar into the chamber. A steel 30 Carbine case neck was typically used.

The grip panels are wide enough the frame could have been expanded to fit a double-stack mag (or something near to it) without affecting the profile, by the way; wasted opportunity.

"They aren't popular because you can't find them."
Obviously; my question is rhetorical, pindering why a subcompact miniature CZ single action was never made. Seems like it'd do as well as something like a P328 or Colt Mustang

I would love a MAC 1950, but I understand there's only like ten in America.

TCB

It was requested I upload some filthy pictures of the gun's bits for everyone;

Main field strip:
-Easier than an R51, Hi Power, five-seven, CZ52, or Steyr-Hahn (I like weird handguns)
-Very similar to a Hi Power/1911 overall, but with Glock/SIG captured spring
-Slide is only pushed back 1/8" to where the barrel begins unlocking (easy to feel for blind-folded field stripping, I suppose) in order to push out the cross-pin, much like the R51

Slide assy:
-Beretta-esque safety. A cylinder with a groove that the firing pin rides tangent in is rotated to a flattened face so it becomes exposed to hammer strike, but blocks the blow otherwise (safety does not disable sear, so it's a quasi-decocker, but beats up the hammer face a bit). Rotates the right way to fire (down), but the 'flag' that sticks up on safe means the gun is not kept this way in a holster (so empty-chamber on a dropped hammer only)
-simple/clever loaded chamber indicator; a pivoting lever pokes down into the top edge of the breech face and is pushed upward by a seated cartridge. Unobtrusive, but larger when activated than most 'pin type' indicators

Fire control group:
-The pivoting trigger drives a sliding/pivoting transfer bar pinned to its free end. The bar only pivots downward so as to disengage from the sear; the magazine safety is an inclined pin which drives it down off the sear unless the pin is pressed out by a magazine body, and an inclined ramp at the free end near the sear is driven down & back* by the slide to disconnect the trigger upon firing.
-The hammer appears, at first glance, to use a tensioned strut rather than a compressed strut. I see a wire loop past the pivot point of the hammer (i.e. it moves up when cocked) at its front end. I believe the SIG P210 is similar in this regard.
-Like the P210, the sear bent surface is at the rear/underside of the hammer, and is actually externally visible when de-cocked**. The sear pivots below the hammer's pivot, and extends around the hammer to the end of the trigger bar (distinctive S-shape, also like the P210). It rotates up and back when driven by the trigger bar, dropping the sear at the opposite end off the sear bent on the bottom of the hammer.
-The entire trigger group, and rear-most chunk of rail, is a self-contained housing which is actually a tad loose in my gun, which is how I can tell. The rear face of the housing fills in the backstrap of the gun (like a 1911's mainspring housing)

Overall, a very cleverly engineered mechanism that appears to operate with so-called 'tensegrity' design principles. The term usually applies to structures, designed to use skeletal members which act only in perfect tension & compression so as to avoid the need for bulky stiffening elements that resist bending/torsion forces ("moments"). Basically building with tie-rods and cables instead of trusses. Likewise, the trigger group of this gun is very much like a series of ball-jointed linkages pushing each other around, each one free to slide or rotate smoothly, performing its job directly along the line of action. This means very little opportunity for binding is present, and contact loads are generally kept as low as possible. The sear bent being so close to the hammer pivot means the break is very abrupt/clean (although leverage means contact loads are high, so the sear is the full 1/4" width of the hammer), and the two ends of the sear lever are about the same length, meaning takeup is reduced to about the height of the sear bent after the initial first stage (caused by an intentional gap between the trigger bar and sear lever at rest). The second stage is probably .03" of pull, fairly heavy due to a clearly powerful hammer spring.

Summary: Action, very much like a link-barreled 1911, bushing-less slide over frame rails like the Hi Power of the same vintage, trigger group very much like the P210 which came afterward, safety arrangement reminiscent of a Beretta 92.

*important to note this arrangement cannot cause trigger slap as a result of disconnecting, unlike cruder arrangements like the CZ52
**sadly, this area between the beaver tail and hammer/sear bent is completely open to the elements, shaped like a funnel, with the sides of the trigger housing also helping to ensure debris is guided neatly down into the action when holstered in a barrel-down orientation. A flap-type holster would probably be a good idea.

Here's a link to a P210 broken down into pieces; I won't be doing this to my 1935A any time soon http://i.imgur.com/nvGYVVZ.jpg

TCB

"Though I only handled a MAB PA15 once it seemed bulkier and chunkier than the BHP or CZ75, but that is subjective I am sure and I did not have either of the others close to hand at the time."
Double stack blowback; it's bulkier, don't even need to see one to know that

"Those are not compelling because there're plenty of better choices available."
Different, maybe, though better is quite subjective. The TT33 is objectively an inferior gun in most ways but firepower (which is moot due to overpenetration of FMJ in both), for example, and the 1911 is a big hunka-hunka steel which can be a bit large for some (the Hi Power more so) and I think carries fewer rounds.

The French had a knack for failing to secure buyers for their domestic arms, which is as much a reason as anything. Were they savvy, they would have made the P210 and not the Swiss, but Manurhin were the only folks doing anything post war, and the French arms industry never recovered (from either war)

TCB