The Doubletap Ammunition .450 SMC rounds work from a standard +P rated .45 ACP pistol.

The Doubletap Ammunition .450 SMC rounds work from a standard +P rated .45 ACP pistol.

Sometimes we shooters do things because, well, why not? It’s as good reason as any, right?

At first glance, the .450 SMC cartridge may appear to fall into the “why not” category. When you start to look at specifics and potential use cases, it can make a whole lot of sense.

What’s a .450 SMC you ask?

What if I told you…

  • That you could launch a .451 160 grain projectile at .357 Sig velocities?
  • That you could blast a standard .45 ACP 230 grain bullet 32 percent faster?
  • That you could break 1,300 feet per second with an 185 grain .45 projectile?
  • That you could shoot a 255 grain hard cast bullet from an autoloading handgun?
  • And most importantly, that you could do these things from your existing .45 ACP pistol?

Sound farfetched? Nope. Assuming you have a .45 ACP pistol that’s rated for +P .45 ACP ammunition, you can shoot the .450 SMC to obtain this type of performance, and more. As we speak, Doubletap Ammunition offers five different loadings of .450 SMC.

Whose crazy idea was this?

In late 2000, a company called Triton launched the .450 SMC. Similar to the .45 Super, one primary difference was the use of a small rifle primer, theoretically allowing more brass in the cartridge base for strength. Alas, Triton didn’t last, and the .450 SMC faded away.

Fortunately for us speed freaks, the Godfather of Boom!, Mike McNett, founder of Doubletap ammunition picked up the rights and tooling for the .450 SMC cartridge, and it’s now commercially available again.

What is the .450 SMC?

Note the small rifle primer on the .450 SMC case on the left.

Note the small rifle primer on the .450 SMC case on the left.

Hopefully, it’s obvious that you can’t simply jam more powder into a standard .45 ACP cartridge case to obtain this type of performance. It’s a little more complicated than that, especially considering that the .45 ACP was designed as a low-pressure cartridge running at about 20,000 psi. There’s margin in the design, but you don’t want to go and drive pressure through the roof.

The solution is to use a different case while keeping the same dimensions. The .450 SMC uses a small magnum rifle primer rather than the standard large pistol primer of the .45 ACP. The small rifle magnum provides plenty of ignition power, but the smaller primer pocket means more brass at the cartridge base, hence a stronger case. As a result, Doubletap Ammunition can load the case with five to six thousand more pounds per square inch of pressure than a standard .45 ACP. Also, the stronger case prevents bulging even in a less-than-ideally supported chamber like a Glock 21.

As of now, Doubletap Ammunition is the only provider of .450 SMC. Founder Mike McNett bought the tooling and is now having a good old time loading lots of .450 SMC in various combinations. And I’m having a good old time shooting it.

Read the rest at AmmoLand!