A look at two similar names that you"ll often discover on the next of 45 caliber ammo boxes and even firearms. Is over there anything girlfriend should recognize when comparing ammo significant 45 Auto matches boxes of comparable rounds significant 45 ACP?

It’s a typical question amongst our customers as soon as looking in ~ ammo for your 1911 or Glock 21 – perform they need to be wary of 45 ACP vs. 45 Auto and also vice-versa?

What’s the Difference between 45 Auto and 45 ACP?

There is no difference in between 45 Auto and 45 ACP. They room in fact one and the same, which leads united state to the point of this article: part cartridges have more than one name. Some have many, in fact, come the suggest where an inexperienced shooter might wonder if they are ordering the exactly ammunition.

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History the the 45 ACP vs. 45 Auto Cartridge


The cartridge dubbed .45 ACP (or .45 Auto) to be designed by the an excellent John Browning in 1904. The gunsmith developed the round for a brand-new .45 caliber semi-automatic pistol the he was also designing for Colt. While Mr. Browning design a great many guns for his own company, that was not ungracious toward Colt who he operated for as well. He because of this didn’t object when his customer decided to surname their new round the .45 Colt automatic Pistol, or .45 ACP because that short.

Shooters knew the round solely as .45 ACP for some time. Yet something exciting happened 1926 with the starting of the Sporting Arms and Ammunition Manufacturers’ academy (SAAMI). The association of American firearm, ammo, and component manufacturers exists to standardize the shoot industry. Their work is helpful: If you were in fee of Hornady, girlfriend would count on SAAMI specs come make certain you’re transforming out the very same sized assets as federal Premium.

SAAMI actions In

Other Names because that 45 ACP

So currently we have a cartridge with two various names. To do matters an ext complicated, the .45 ACP/.45 Auto is likewise known in Europe by its metric name 11.43×23 mm, in France particularly as the 11 mm 43, and also in Argentina together the 11.25 mm. It’s likewise simply dubbed the 45 by shooters who describe it a lot.

So, not only is 45 ACP vs. 45 Auto the same specific cartridge, it’s additionally the exact same as 11.43x23mm or 11mm 43, or 11.25mm.

But Wait, There’s More!


The .45 ACP is no the only round v multiple names. Take it the 9x19mm Parabellum as one more example. Georg Luger designed it in 1901 together the companion cartridge because that his employer’s Pistole Parabellum. So, its name is essentially a metric measurement plus a trademarked name. SAAMI wouldn’t have that. So, they change the name it come 9mm Luger for your purposes. In ~ the end of the job they’re quiet the same cartridge.

When to buy ammunition, that is crucial to identify whether or not two differently named cartridges space identical. .38 Special and also .38 at sight both sound similar with positive words in their titles, yet they are in reality nothing to execute with one another. The .223 Remington and also 5.56×45 NATO share the same dimensions, however the last creates a significantly higher chamber pressure. The .300 Winchester Magnum and also the .300 Weatherby Magnum haven’t also got the same parent casing.

If friend are ever in doubt, a small time top top Google will collection matters directly quickly. Because that future reference you may also consult this table with few of the most well-known cartridges in America accompanied by their other typical names.

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Common NameOther name(s)
.17 HMR.17 Hornady Magnum Rimfire
.22 long Rifle.22 LR, 22
.22 Magnum.22 WMR, .22 Magnum, .22 WMRF, .22 MRF, or .22 Mag
.22 TCM.22 Tuason Craig Micromagnum, 22TCM
.222 Remingtontriple deuce, triple two
.223 Remington.223 Rem
.223 WSSM.223 Winchester Super brief Magnum
.30-06 Springfield.30-06, .30 Gov"t "06
.30-30 Winchester.30 Winchester facility Fire
.300 AAC Blackout300 BLK, 300 AAC Blackout, 7.62x35mm
.300 RUM.300 Remington Ultra Magnum, .300 Ultra Mag
.300 victory Mag.300 Winchester Magnum, 300WM
.300 WSM.300 Winchester quick Magnum
.308 Winchester.308 Win
.32 ACP.32 Automatic
.32 S&W.32_
.357 Magnum.357 S&W Magnum
.357 SIG357 Sig, 9x22mm
.38 Special.38 blacksmith & Wesson special , .38 Spl, .38 Spc
.38 Super.38 supervisor Auto
.40 S&W.40 cal
.44 Magnum.44 Remington Magnum, .44 Mag
.44 Special.44 S&W Special
.45 ACP.45 Auto, 45
.45 Colt.45 long Colt, .45 LC
.45 GAP.45 Glock
.45-70 Government.45-70, .45-70 Govt.
.50 activity Express.50 AE
.50 BMG.50 Browning device Gun, 50 Browning, .50 cal
10mm Auto10mm, 10mm Automatic
5.56×45mm NATO5.56 NATO
5.7x28mm5.7 x 28, 5.7
6.5mm Creedmoor6.5 Creedmoor, 6.5 CM, 6.5 CRDMR
7.62x39mm7.62 Soviet
7.92x57mm Mauser8mm Mauser, 8x57mm, 8 x 57 IS
7mm RUM7mm Remington Ultra Magnum
7x57mm Mauser7mm Mauser, 7x57mm , 7 x 57, .275 Rigby
9×18mm Makarov9mm Makarov, 9x18mm PM
9mm Luger9x19mm Parabellum