Long piece, so there's a lot to work through — but the parts worth actually discussing are the mechanical history, the criminal adoption that led directly to the NFA, and the sheer speed at which a brand-new weapon class went from "concept proven in a trench" to "defining infantry tactics for four decades."

The invention of such a compact, highly mobile firearm capable of rapid repeating fire had been sought for nearly 900 years of military history.

Nine hundred years is a long runway. The pepperbox guys were solving the same problem as Hugo Schmeisser — they just didn't have the metallurgy, the cartridge technology, or the right war to pressure-test the answer. The MP 18 shows up in 1918 and the problem is essentially solved within a generation.

Thompson became the first person to label and market a weapon under the 'submachine gun' designation — a term that would define the entire weapon class.

Worth sitting with that. The Germans got there first mechanically — the MP 18 beat the Thompson to combat by months — but Thompson named the category. That's why your Form 4 says what it says when you're transferring a registered MAC-10, not a "Maschinenpistole."

This notoriety had consequences: the perceived popularity of the Thompson with violent criminals was among the primary justifications cited for passage of the National Firearms Act by Congress in 1934.

"Perceived popularity" is doing a lot of work in that sentence. The actual number of Thompsons in criminal hands was a fraction of what the newspapers suggested — but the Valentine's Day Massacre had already run in every paper in the country, and that imagery was enough. Every NFA discussion at the gun store counter eventually traces back to this exact moment.

The MP 18's basic design formed the basis of most submachine guns manufactured between 1920 and 1960

The Sten, the PPSh-41, the Lanchester — all downstream of Schmeisser's open-bolt blowback layout. Simple, cheap to produce under wartime conditions, reliable enough. When the Soviets needed millions of guns fast, they didn't reinvent anything — they just stamped out a variation on a 1918 German design. That's how good the original solution was.

In an open-bolt, blowback design: when the weapon is cocked, the bolt is held fully rearward by the sear. When the trigger is pulled, the bolt travels forward under spring pressure, strips a round from the magazine, chambers it, and fires — all in a single continuous motion.

If you've ever run a registered MAC or a DIAS-equipped lower, you already understand this mechanically — but it's worth knowing why open-bolt was the standard for so long. No cook-off risk on sustained automatic fire matters a lot more when you're running 600 rounds per minute than when you're shooting a stage at a match. The tradeoff the article mentions — that hard knock to the stock could fire the MP 18 — is exactly why later designs added the bolt-lock notch on the cocking handle.

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For those of you who've had trigger time on registered subguns or have shot pistol-caliber carbines in competition — how much do you think the 9mm vs. .45 ACP split still matters for the SMG role today, or has that argument been settled by the modern +P and hollow point era?

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Read the full article in The Handbook → | By The Boise Gun Club Team