A look in ~ two similar names that you"ll often uncover on the side of 45 caliber ammo boxes and also even firearms. Is over there anything friend should understand when compare ammo significant 45 Auto matches boxes of similar rounds significant 45 ACP?


It’s a common question amongst our customers as soon as looking at ammo for their 1911 or Glock 21 – execute they must be wary of 45 ACP vs. 45 Auto and vice-versa?

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

There is no difference in between 45 Auto and 45 ACP. They room in fact one and the same, i m sorry leads us to the allude of this article: some cartridges have more than one name. Some have actually many, in fact, to the allude where one inexperienced shooter might wonder if they space ordering the exactly ammunition.

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History the the 45 ACP vs. 45 Auto Cartridge

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The cartridge called .45 ACP (or .45 Auto) was designed through the an excellent John Browning in 1904. The gunsmith developed the round for a brand-new .45 caliber semi-automatic pistol the he was likewise designing for Colt. When Mr. Browning draft a an excellent many weapons for his own company, the was not ungracious towards Colt who he operated for together well. He as such didn’t object when his customer decided to surname their new round the .45 Colt automatically Pistol, or .45 ACP because that short.

Shooters knew the round specifically as .45 ACP for part time. However something interesting happened 1926 v the starting of the Sporting Arms and Ammunition Manufacturers’ academy (SAAMI). The association of American firearm, ammo, and component manufacturers exist to standardize the shooting industry. Their work-related is helpful: If you were in fee of Hornady, friend would rely on SAAMI specs come make certain you’re turning out the same sized products as commonwealth Premium.

SAAMI procedures In

Other Names for 45 ACP

So currently we have a cartridge v two different names. To make matters much more complicated, the .45 ACP/.45 Auto is likewise known in Europe by its metric name 11.43×23 mm, in France specifically as the 11 mm 43, and also in Argentina as the 11.25 mm. It’s likewise simply referred to as the 45 by shooters who describe it a lot.

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

But Wait, There’s More!

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The .45 ACP is not the only round with multiple names. Take the 9x19mm Parabellum as an additional example. Georg Luger designed the in 1901 as the companion cartridge for his employer’s Pistole Parabellum. So, its name is basically a metric measurement plus a brand name. SAAMI wouldn’t have actually that. So, they renamed it come 9mm Luger for their purposes. In ~ the end of the work they’re still the same cartridge.

When to buy ammunition, it is essential to recognize whether or no two differently named cartridges are identical. .38 Special and .38 at sight both sound similar with positive words in your titles, but they room in reality nothing to execute with one another. The .223 Remington and also 5.56×45 NATO share the same dimensions, but the last creates a significantly higher chamber pressure. The .300 Winchester Magnum and also the .300 Weatherby Magnum haven’t also got the very same parent casing.

If girlfriend are ever in doubt, a small time ~ above Google will collection matters straight quickly. Because that future reference you may likewise consult this table with several of the most famous cartridges in America add by their other usual 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 short Magnum
.30-06 Springfield.30-06, .30 Gov"t "06
.30-30 Winchester.30 Winchester center Fire
.300 AAC Blackout300 BLK, 300 AAC Blackout, 7.62x35mm
.300 RUM.300 Remington Ultra Magnum, .300 Ultra Mag
.300 win Mag.300 Winchester Magnum, 300WM
.300 WSM.300 Winchester short 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 one-of-a-kind , .38 Spl, .38 Spc
.38 Super.38 super 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 lengthy Colt, .45 LC
.45 GAP.45 Glock
.45-70 Government.45-70, .45-70 Govt.
.50 activity Express.50 AE
.50 BMG.50 Browning machine 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