Ask Ian: Single Feed vs Double Feed Pistols

Asked by Tyler on Patreon: “Why are there so few double stack/double feed handguns? I can only think of a couple off the top of my head. It makes the worst part of handgun shooting (loading the magazines) a complete non-issue.”

There are a series of interacting considerations when choosing between single feed and double feed.

Single Feed:
– Magazines are less reliable; constricting from two columns to one adds friction (this is magnified as capacity increases)
– Firearms are easier to design; the cartridge is always presented in the same place
– Pistol slides may be slightly narrower

Double Feed:
– Magazines are more reliable (also less susceptible to a bit of dirt fouling them)
– Guns are harder to design; must accommodate two different feed positions
– Guns must be a bit wider (immaterial in rifles)

These elements taken together lead to predominantly single feed magazines in pistols and double feed magazines in rifles, although exceptions exist to both.


  1. If I may, Ian… Missed point in this presentation is the sort of cartridges typically used in the two.

    Rifle-class cartridges are easier to use double-feed magazines with because they’re generally more tapered and have a pointed bullet; pistol cartridges are usually straight-walled cases, and a much flatter projectile. The feed ramps on a pistol have to accommodate that, and they’re usually space-critical in design. If you had more pistol projectile and case designs that looked like rifle cartridges, you would almost certainly see more people designing double-feed magazines for them. The tradeoffs in terms of the width of the mechanism have a lot to do with why the designers make the choices they do.

    Also, the reason you had double-feed magazines on the old stripper-loaded pistols like the C-96 and the various Austrian ones like the Roth-Steyr wasn’t strictly because they wanted to use that Mauser design everywhere: The stripper loading made double-feed mandatory, because you can’t fill a single-feed magazine with a stripper clip unless you resort to some really flaky moving feed lips, which I think I’ve only ever heard of vaguely in someone’s patent. I’m not an expert, by any means, in older semi-auto pistols, but I’ve never seen a stripper-fed single-feed design anywhere that actually made it into production.

    • It also has to do with not fixing what’s not broken.
      At this point, the geometry of reliable single feed magazines and reliable feed ramps are well known. Designers haven’t to spend time, and money, to redesign those parts.
      If they choose double feed instead, they have to design magazines and feed ramps from scratch, and that takes time and money.
      That’s why it seems are mainly manufacturers that don’t have to compete on the market and/or are government founded that nowadays decide to invest in designing double feed pistols (see Norinco CF98, GSh-18, MP-443 Grach…)

    • Err, Kirk, you ever heard of a Mosin rifle? It has a single stack stipper-loaded magazine. 37 million copies, the world over. Ever seen the Roth-Steyr M.7 or M.12 Steyr-Hahn, you write about? Both are stripper-loaded single stacks. Yes, loading a single stack from a stipper clip is more tricky, but still doable

  2. This is why single stack magazines a la 1911/Walther P38/P1 and almost all pocket pistols are better-simple and straightforward. Also, to mess with why I shoot revolvers- no pesky magazines

    • Pocket pistols were traditionally single-stack for compactness’s sake, but even they’re rapidly losing ground since companies found ways to build concealable pistols around double-stacks. Except for historic firearms like you described, essentially zero manufacturers, agencies, or services in 2022 believe single-stack mags are better for new service pistols.

      • Except people who believe the 1911 type pistol is the best ever designed- if it is not, why are virtually all manufacturers of handguns making them?

        • Because the 1911 is very popular among amateur shooters in the US, which is the largest market of legal handguns? It still does not change the fact the 1911 is no longer chosen by virtually any agencies or services as a service pistol. Instead they prefer pistols with higher capacity double stack magazines.

        • I already acknowledged those exceptions. The 1911 (and Luger, P210, etc.) inspire nostalgia, and also impress with their quality and ergonomics. They’ve also lost significant market share, especially (as Euroweasel noted) among professionals. One huge reason 1911s remain popular in single-stack configuration is because they’re built around the .45ACP cartridge; between that and the screwed-on grips, they are morbidly obese in double-stack form (even for my large hands). If someone developed one with a grip frame for common double-stack 9mm mags, they’d sell like hotcakes.

          None of which changes the truth I noted before: practically no one, designing a “new service pistol” (one that doesn’t need to be ultra-compact) has come to the conclusion that single-stack mags are better, in a very long time.

          • Fact is that double stack / single feed reliable magazines are harder to design but, at this point, they have long been designed. That effort had already been done.
            If a manufacturer wants an absolutely reliable, proprietary, double stack / single feed magazine, he only has to call Mec-Gar, or similar, and ask for a magazine identical to that of the Beretta 92, CZ75, Tanfoglio large frame… with only a bit of difference (like the position of the magazine release slot) to make it “proprietary”.

          • Fact is that double stack / single feed reliable magazines are harder to design but, at this point, they have long been designed.

            I couldn’t agree more. On numerous gun boards, any product that takes Glock mags always triggers a chorus of Glock-mag haters. They remind me of guys who drove a slow-accelerating automatic in 1950, resolved never to drive a “damn slushbox”, and never let the fact that countless modern automatic cars out-accelerate any 1950s manual shake that prejudice. Yes, it’s harder, but it’s absolutely been done. I’ll take Glock extendos’ 445-2-5 review record on Midway (from people who’ve actually used them) over “Hurr, durr, STEN mags” whining any day.

          • @dogwalker
            “…he only has to call Mec-Gar, or similar…”

            Exactly. The market is specialized and structured such no pistol maker has to spend time on their own magazine design. My guess is Mec-Gar makes half of worlds pistol magazines.

            At the present time the single feed mag is the king. Main problem with double feed is to provide reliable feed ramp(s) at barrel lug with conventional Browning lockup. There is not enough space for it.

          • @ dp
            It’s a kind of “economic inertia” that exists in many branches of industry. Where there is a potentially better solution than the one currently used, but the reality is that the currently used one is so well know, there is so much technical literature on it, there are so many manufacturers that already produce it, and refined it over the years to almost perfection, there are so many mantainers able to work on it, that it would take a huge investment only to make the “potentially superior one” to work as well as the existing one, that only requires the effort of choosing from a catalog.

          • For 1911, one solution is STI 2011 type of added plastic magwell,
            with which you could do away with screwed in wood grips, thus you get more space inside.

          • Storm,
            That is very true, but as far as I can tell all existing 2011 magwells are still wed to the double-.45ACP form factor, which is ridiculously bulky for 9mm.

            Since it is removable, and plastic, the 2011 grip frame seems like a fairly easy route to get to accepting common 9mm-size magazines, with no real complicating factors (other than the need for a new trigger bow).

          • Hmm, 1911 is known for its grip angle which is I believe somewhat fixed, or you get different, odd looking gun (like if you were change it on Luger…)

            Now it needs to be researched what is the angle of these usual wonder nine magazines, that are most common on the market, if the goal is to use cheap non specialized magazine in this double stack 9mm 1911

          • Storm,
            The 1911 is known / loved for its grip angle, which is why this grip angle set the standard for nearly all US pistols. The Glock is distinctive for having a sharper, Luger-like angle that makes it feel different from practically everything else.

            Even with a Glock mag, though, it is possible to deliver a (somewhat) 1911-like angle by changing the external curves, like in the Polymer 80 frames. It would be easier still for other common mags, which are not only less angled, but also thinner (metal) allowing for more “padding” of the grip shape without becoming too thick overall.

          • There are probably some design quirks in 1911 slide underside or top of frame beneath it, as looking at 9mm double stack, that sti 2011, magazine is unusually tapering at the top, almost to single stack type.

            But, what is your overall goal here, you would want to have a 1911 clone that accepts completely regular magazines? You think that would be a huge market pleaser?

          • Storm,
            In terms of overall goal, I see it as one subset of a false dichotomy afflicting the whole pistol market: You can get a modern pistol (but only with a wet-sponge striker trigger, tiny controls, etc.) or the brilliant ergonomics of the 1911 pistol (but only in exact replicas with all the quirks no one has used in a new design for 50 years), but never the best of both. By the same token, you can get a 1911 with a capacity that Browning himself rendered obsolete in 1928, or a 2011 / 1911A2 with a ridiculous gigantic grip, but never a 1911 with an ergonomic and concealable double-stack grip (even though millions of other pistols have them in 2022).

            Some modern-pistol fans hate 1911s, and some 1911 fans hate “tupperware”; however, many shooters enjoy both, so I do think a best-of-both (BoB) would be a “market pleaser”.

            Recently, Smith and Wesson made a reasonable effort with their CSX, except it has a heavy trigger (defeating the whole point of an SAO). I customized my own to a glass-rod 3.25lb, so I’m quite content; the only thing missing now is longer mags, grips, and slides (to offer the BoB across the range of pistol requirements). I still think it’s bizarre that the factories don’t offer a 2011 like I described; if it really does require a “2 into 1” magazine, the P365’s is set up that way.

          • It think the problem is in the thickness, stock 1911 slide is thinner then some other guns, thus why they use these strange top tapering thin 9mm mags.
            Maybe with only a little fattening, out of the 1911 spec norm, it could be redone for “normal” mags.

            Unless that causes somehow the change in exceptional ergononmics or visuals, but then we are at dead end of what can be done. Anyhow, its worth experimenting

          • Storm,
            I think I understand your concern (please correct me if I’m wrong): The 1911/2011 has a somewhat narrower slide than e.g. a Glock, and also has to fit the magazine between full-length rails that run inside the slide. Thus, it cannot fit something like a Glock mag, and uses a mag that constricts at the top not just to a single-position feed, but a section that is vertical / single-column for about the height of one round.

            My point was that the P365 also has a narrow(er) slide, and also has full-length inside rails, and uses a very similar (double into single column for the top round) mag that might work in a 2011 slide.

          • I’ve investigated 365 mag before your newest comment, found out that theres actually a controversy with it, they, Sig, are in litigation with springfield armory, as magazine has some patented features, made specifically for these small sized pistols.

            Whats funny and almost absurd, that main feature is a most simple stamping on the front, less then inch of height, basicly in a portion where all these double to single mags have diamond shaped stamping, this one has front stamped and ramped also.
            So, theoretically (for now) in that case you could use such mag type only if paying royalties to SIG, which constricts third party magazine makers like mecgar, etc.

          • Yes, they’re quite the patent trolls for un- or pseudo-original features that somehow slipped through USPTO.

            I wouldn’t copy their mags, just use them – like everyone who makes Glock-mag-compatible pistols and carbines. They aren’t cheap, but they’re cheaper than STI’s.

          • Now when at it, getting into patent-industrial quirks, I wonder legally if you can do that, and how; would Sig sold you enough amount of mags for your sustained production.
            I suppose they would try to milk you, if concluded the mag is a vital to this 1911 construction, thus most likely selling you way above usual market price, maybe even sabotaging you by bottlenecking your mag production (no mag-no guns), unless you strike a deal of making your own copy – which also would not be cheap.

          • Storm,
            I’ve never seen such a thing. Manufacturers are justly compensated for their IP when you pay market price for their products; additionally, they receive side benefits as e.g. Glock-mag carbines, Phillips screws, or Windows computers move to become common industry standards.

            The optimum situation would be SIG (who already produces both 1911s, and modular P365 and P320 grip frames for those magazines) becoming the producer of 2011 grip frames for their magazines 🙂

          • The thing with glock magazines and third party carbines is that Glock profits from selling magazines as it does not see the product a threat for from their own pistol line.
            Coming with 1911 double stack design that finally mows the quirks and starts selling cheaply like hot cakes, is a direct competitor to SIG, and incentive of not selling wonder mags to the third company is there.
            To give example, if Glock comes up with their own carbine, in that case the 3rd parties making such, using g.mags are direct competitors.

            So in the end,
            only win win situation for market would be as what you proposed in last paragraph.
            Though for a single company there is a phenomenon of cannibalizing, where one new product causes fall in sales of their another product (which is btw. their complete trademark and brainchild, not like old 1911 design from Browning), so also that risk factor.

            So, it could seem to some onlooker we’ve put maybe too much discussion into all this, but in the end lot of variables beside good “revolutionary” design influence if something fails on the market, or in production. Hudson h9 is a great unfortunate example…

          • Possibly, but it wouldn’t directly compete with any of SIG’s existing products. Consider that not only carbines, but numerous pistols using Glock mags have sprung up since their earlier-generation patents expired. Many are either better / upgraded, or similar but much cheaper than their own pistols. Glock hasn’t stopped supplying the mags, and I’m not sure how they could.

            Besides the earlier possibility I suggested, there are several others (mostly positive) for SIG. Offering a P365 with “custom shop” trigger, larger safety, and an aftermarket grip frame matching their 15rd mag would check the same boxes.

          • Hmm, come to think of it, its a good question how many pistols, as in real pistol/handgun form take Glock mags, beside Glock. A short search yields me vast amount of cases “Pistols”/”PDWs” that are actually shortened ar15s, with magwell accepting such mag. And some carbines ofc.
            Both are no real competitors to Glock line of pistols, all their sales are maybe under 10% of what Glock solds.

            As for SIG, having 9mm 1911 with full round capacity like some other of their guns, is a direct harm that the other gun will not be bought, but only this 1911.
            Not having it in stock, there is a chance one will buy 2 guns, to cover everything, both modern stuff (maybe for carry if he feels better with more rounds) and venerable low capacity 1911, for his range/collection pleasure.

          • There are numerous “Gucci Glocks” from ZEV and others. There are Polymer 80s (Glock copies with similar prices and different grip ergonomics), and some cheap Turk knockoffs. All are Glockish pistols and not “braced pistols”.

  3. I would also look at the matters of environment and coincidence in early automatic firearm design. Borchardt and then Mauser were dealing bottle-necked cartridges, thus somewhat rifle-shaped. Borchardt had worked at Sharp’s and had experience with Mr. Lee’s box magazine. Mauser, as Mr. M. mentions, went with what he already had made for rifles, I think not just because he held the patent but because it was what he (and the Fiederle Bros.) were used to. The bottle-necked cartridge was important but coincidental — it was the right amount of power and it could be easily headspaced. Bergmann’s 1894 pistol side-loaded a Mannlicher clip because that was the best idea he had available. The (relatively) straight-walled pistol cartridge, I think derived from revolver experience, was also the low-powered cartridge — Bergman (a little tapered?), Mannlicher, and then finally J.M. Browning’s 7.65 x 17, basically a rimless .32 S&W smokeless. Was the Savage automatic –“Ten rounds quick”– both double-stack and double-feed? Thank you for your input here.

  4. Another advantage for double feed magazines if they can be loaded from stripper clips. This is probably more important in military rifles.

  5. “(…)These elements taken together lead to predominantly single feed magazines in pistols and double feed magazines in rifles, although exceptions exist to both.”
    One another thing which might influence state of affairs is that some double-stack magazine automatic pistols were derived from single-stack magazine automatic pistols, e.g.:
    Neuhausen Pistol M/49 -> SIG-Sauer P220
    Makarov PM -> PMM
    S&W Model 39 -> S&W Model 59
    Using (already supported) single-feed lessened amount of alteration which were required when compared to using double-feed magazine.

  6. Interestingly enough so far nobody tried the ‘best-of-two-worlds’ solution of a wedge-section double-stack in semi-automatic pistols, although it is a popular solution in submachine guns: Czech Sa-23/25, Sa-24/26 and Swedish K – they all had a wedge-section double-stacks, allowing the +/- center feed from two sides and stripper loading. And if that works in an SMG, why would it not work in pistols?

    • Hmm, good question,
      maybe because of the angle ?
      In SMGs they are ALWAYS straight, in pistols they would need to be angled as a grip, and with that triangular profile, maybe it would be a failure in reliability

  7. A couple of thoughts

    Perhaps a better division between “double feed” and “single feed” would be the feed lips being wider or narrower than the cartridge case they’re designed to take.

    The reason being that there is a gradation between truly single column and double column magazines.

    Mauser used to have a range of different magazine boxes of different internal widths and tapers to suit different cartridge cases

    I’ve still to work out the design parameters that Mauser was using for box width.

    Smaller gunsmiths building rifles chambered for big fat cases, would sometimes use the original width magazine box, with a modified follower and feed lips.

    an example would be the .425 Westley Richards with its .550″ diameter case body

    Technically, those modified mags were still double stack double feed, but you’d be hard pushed to see two cases through the feed lips.

    Expanding on Ian’s comments about single stack magazines in precision rifles

    Single stack magazines were used in some very small rifles, eg the Brno ZKW 465 and its German twin the Krico 400, simply due to size constraints

    However there’s also the use of single stack mags in the full sized Shultz and Larsen M54J and Remington 788, to minimise the amount of metal removed from rear locking bolt action receivers.

    The shultz and Larsen actions were also used as the basis for the early. 378 Weatherby rifles

    Single stack Mags continued to be used by Krico on the M600, where the narrow magazine resulted in less loss of receiver rigidity and bedding area compared to a double stack mag.

  8. “(…)– Guns must be a bit wider (immaterial in rifles)”
    Apparently this can be also countered by using thinner cartridge, like is done in FN FIVE-SEVEN.

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