Capacity, Capacity, Capacity. Capacity often seems to be the equivalent of location in real estate with new handgun releases often including higher capacity magazines or listing larger capacity as one of the main selling points. The advances in double-stacked compacts and subcompacts have revolutionized the carry market in the past decade. Where previously small easily concealed handguns usually had a maximum capacity of 5-7 rounds, today that capacity is closer to 11-16 rounds in similar-sized guns. Though many would rightfully argue it is more about shot placement, the value of higher capacity is hard to argue with. My instructing partner puts it this way: “If I am ever killed in a gunfight, I don’t want it to be from a lack of shooting back.”
Higher capacity has some limitations. The more rounds carried, the greater the weight and usually, the larger the firearm. For example, the dimensions of the standard Sig Sauer P365 with 10+1 round capacity are 4.3” high, 5.8” long, and 18.5 oz loaded weight, while the P365 with 12+1 has a height of 4.7” and weighs 19.8 oz loaded. The simple fact is with increased capacity comes increased weight and size. Beyond just carrying or using a larger handgun what are the options for increasing capacity?
The clearest solution is to add additional loaded magazines to your carry routine. Personally, I’m a fan of Snag Mags carriers for my extra magazines. These simple holders are made to retain a magazine in any pocket and include a small hook allowing for easy access to the magazine while leaving the carrier behind in the clothing. Beyond such pocket devices, there are numerous magazine pouches, both inside the waistband (IWB) and outside the waistband (OWB). Carrying an additional magazine also provides quick alternatives if your primary magazine fails or experiences a malfunction. Just make sure to practice your reloading, malfunction clearances incorporating a new magazine, and accessing your extra magazines if this is your choice for increasing capacity.
Magazine Extensions
Adding magazine extensions can increase your immediate capacity in your primary magazine and can also provide additional capacity if added to additionally carried magazines. Magazine extensions are primarily aftermarket extensions and work by replacing the original magazine’s baseplate. There are extensions available for most magazines on the market and typically add between two and five rounds to the capacity of the magazine. Smaller extensions will often use the same magazine springs while larger extensions may include a longer and stronger spring for use with the extended magazine. These extensions can be lighter-weight polymers or specifically designed out of heavier-weight metals. Heavy magazine extensions add to the overall weight of the gun (potentially to help with felt recoil). Companies making such extensions include Tyrant Designs, Zev, Warne, and Taran Tactical.
Though I do not use any extensions on my concealed carry guns, I have used Taran Tactical +5 round extensions on Glock 17 that I often wear when conducting training classes. This gun is holstered in an OWB leather and Kydex holster and the extensions included an additional spring designed to be 10% stronger and fit the new extended length of the magazines (from 17 rounds to 22 rounds). Though the extra weight and height would be an issue if trying to conceal, I find it to not be an issue when open carrying. Additionally, at least for me, I find the additional weight helps to further balance the gun in my grip and reduce perceived recoil.
Truly High-Capacity Options
Though many state laws within the United States define a high-capacity magazine as anything holding more than 10 rounds, the more widely used definition is any magazine specifically designed to increase the capacity of a firearm over its usual (stock) capacity. Outside of an apocalyptic event, the everyday use of magazines specifically designed to greatly increase the capacity of a handgun is highly dubious. The increased weight, restrictive size, and balance issues due to doubling the weight at the rear of the gun all result in issues that make such devices more range toys than tactical options.
That said there is nothing wrong with cool range toys and there is a certain joy to be found mag dumping 33, 40, or even 50 9mm rounds from a Glock 17 without having to reload. The further inspiration for my testing of high-capacity magazines was that during the ammo shortages of 2020-2021 I picked up lower quality 9mm that is no longer in rotation as my preferred ammo options returned to first being available and recently have returned to acceptable prices. This resulted in having about 500 rounds of ammunition (from somewhere in Eastern Europe) that I am unlikely to use now that my stockpiles of ammunition are back to pre-2020 levels. Though it has been reliable (it goes bang when you pull the trigger) it does vary greatly in velocity (900-1200 feet per second) and is very dirty (think of fireworks spitting from the barrel).
I could not bring myself to completely mag dump. To aid in the testing I set up a few parameters including always shooting at 30’, keeping my rounds in a 12” area, and shooting quickly using a flash sight picture – each time follow through brought the recoiling gun back on to target immediately taking the next shot. For the purposes of these tests, I compared four different high-capacity 9mm magazines for the Glock 17 (also useable by the Glocks 17L, 17C, 18, 19, 19X, 26, 34, 45); the KCI Gen 2, 33 round magazine, the SGM Tactical 33 round magazine, the ETS 40 round magazine, and the KCI 50 round drum magazine. The first three are all traditional stick magazines with the KCI and SGM looking like traditional black Glock Mags with the traditional round windows (31) at the back of the magazine. The ETS magazine, though also a stick magazine, is a fully enclosed (no round holes in the back) see-through polymer. The KCI drum magazine is an opaque black polymer and includes a spring assist lever to facilitate easy loading.
Loading
The KCI and SGM required a fair amount of force to hand load past the mid-20s. The KCI topped out at 31 rounds and the SGM at 32. The ETS loaded a little easier with greater force being needed past the mid-30s and ended up taking 41 rounds (1 round over advertised). With the KCI drum magazine, each push of the loading lever initially allowed 2-3 rounds to be easily added. However, past 20-30 rounds this reduced to 1-2 rounds, and past 40 rounds each additional push resulted in 1 round loading and occasionally required a few quick shakes of the magazine to settle the currently loaded rounds to make room. The total load in the drum ended up 2 over advertised at 52. Full details and weights are presented in the table below.
Subjectively I found the heavy magazines allowed me to better control the felt recoil resulting in a faster rate of fire with the 40-round ETS and the 50-round KCI drum magazine. In the case of ETS, my rate of fire across the 41 rounds resulted in a rate of fire of 2.56 rounds a second, and with the KCI drum magazines 52 rounds, I was even faster at 3.25 rounds per second. All four magazines ran flawlessly with no issues or malfunctions. Overall, I preferred the ETS 40-round magazine for just putting rounds down range. It was the cheapest, second largest capacity, second easiest to load, and second fastest rate of fire. The KCI drum magazine would be a better option if you struggle with loading (or just really need those 10 or so extra rounds). Though the process of loading slowed towards the last rounds it was still very easy to use with the loading lever. There are many methods to increase capacity, just make sure you are choosing the one that is right for you and your planned use.
