July 20, 2022. The.223 Remington is the most popular centerfire rifle round of the Western Hemisphere. Its metric match, which is the 5.56x45mm, is also very popular. Many people use “.223 Rem”, “5.56×45” and “.223 Rem”. Although they are often interchangeable, there are significant differences in the specifications of the original.223 Rem cartridge and the 5.56x45mm ammunition, as adopted by NATO armies and the U.S. military. The default chamber throats of the.223 Rem are slightly different, and the.223 Rem is rated as 55,000 PSI vs 62,366 PSI in the 5.56x45mm. *.223 Rem vs 5.56x45mm — Key Differences
LuckyGunner.com has published a very comprehensive article on the subject. ** This required extensive testing with pressure monitors of 5.56x45mm ammunition in.223 Rem chambers. These tests revealed the maximum pressures. Here’s one of the ammo testing charts:NOTE: Federal XM855 5.56mm ammunition was observed in a.223 Rem chamber. It exceeded the.223 maximum pressures but not by a large amount. The ninth shot (the “red line”) was an underpowered cartridge that exhibited significantly lower velocity/pressure than the other rounds. It was therefore excluded from the average velocity/pressure numbers for this chamber. LuckyGunner also fired 5.56x45mm NATO-chambered AR15 guns with.223 Rem ammunition. As you would expect, the peak pressures were significantly lower, but the .223 Rem ammo still cycled the semi-auto AR-platform rifle perfectly well:UltimateReloader.com Explains .223 Rem vs. 5.56x45mm
Gavin Gear, UltimateReloader.com’s friend, has created a detailed 12-minute video explaining the differences between the 5.56x45mm and.223 Rem cartridges. This video explains the specifications of the cartridges and key considerations for hand-loaders. Gavin also answers the question, “Can I shoot 5.56x45mm ammunition in my.223 Rem Chamber?” Gavin’s video definitely deserves to be seen. This is actually one of the most watched videos Gavin has ever made — it has been viewed nearly 4.5 million times online. What is the 5.56x45mm NATO Cartridge exactly?
NATO, a rimless, bottle-necked intermediate cartridge that measures 5.56x45mm, was developed by FN Herstal and standardized by NATO. It includes the SS109, SS110 and SS111 cartridges. It is a standard cartridge that NATO forces can use.
Maximum pressure (EPVAT): 430.00 MPa (62,366 psi)
Maximum pressure (SCATP 5.56): 380.00 MPa (55,114 psi)
Case length: 44.70 mm (1.760 in)
Rifling twist: 178mm or 229mm (1 in 7 In)
Parent case:.223 Remington, M193.Ammo-Maker Federal premium Compares to.223 Rem & 5.56x45mm
Federal Premium, an ammunition manufacturer, has posted a video explaining the differences between NATO 5.56x45mm NATO and.223 Remington. Federal states that excessive pressures may occur when firing a 5.56x45mm NATO cartridge in a standard.223 Remington chamber. A leading gunwriter has addressed the issue of shooting 5.56x45mm ammunition in.223 Rem chambers. He recommends caution (for more information, SEE pressure tests at LuckyGunner.com). “I have received a lot of questions — many from first-time AR-type rifle buyers — regarding the.223 Rem cartridges and the 5.56×45 mm NATO cartridges. Can I shoot 5.56×45 NATO in my.223? These cartridges are the same? The two cartridge cases look identical from the outside. The main differences between the NATO 5.56x45mm cartridge cases and the.223 Rem. 5.223 Rem. has a chamber pressure of 55,000 PSI, while NATO 5.56x45mm NATO operates at 60,000 PSI. The 5.56’s chamber is slightly bigger than the.223 Rem. The chamber is also slightly larger than the.223 Rem’s 5.56×45 mm chamber. What does this mean? 5.56x45mm NATO should not be shot from a rifle chambered with.223 Rem [with standard short throat]. You should also be aware that although some.223 Rem ammunition may not cycle reliably through certain AR-style AR-style Rem rifles, it will usually. Current.223 Rem ammunition has never been a problem for me. A 5.56mm AR-style rifle can handle loads. American Rifleman Editor Mark Keefe* The NATO 5.56x45mm NATO case can withstand up to 430.0 MPa (62.366 psi). Piezo service pressure. The U.S. SAAMI lists the Maximum Average Pressure (MAP), for the.223 Remington cartridge at 55,000 psi (379.2MPa) piezo pressure, with deviations of up to 58,000 psi (599.9 MPa). The 5.56x45mm NATO chamber has a longer throat before the bullet contacts the rifling. This results in lower pressures when using 5.56x45mm NATO ammunition. 5.56x45mm NATO can be used in rifles that are chambered for.223 Remington. The bullet will then be engraving the rifling. This can cause pressures to rise beyond SAAMI Max levels. NOTE: The C.I.P. C.I.P. standards The civilian.223 Remington chamber is much closer to the military 5.56x45mm NATO Chamber. ** The full LuckyGunner article worth reading is highly recommended. It also provides specifications for several.223 Rem types and compares the original 5.56x45mm NATO and the modern.223 Wylde chamberings.
Similar Posts:Tags :.223 Rem. C.I.P. Rem, .223 Remington, 5.56x45mm NATO, Gavin Gear, LuckyGunner.com, SAAMI, Ultimate Reloader
