By Tom McHale

USA –-(Ammoland.com)- 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 Round?

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.

Performance

When it comes to understanding relative cartridge performance, there’s one place I go first. The Cartridge Comparison Guide, written by my friend and mega gun geek Andrew Chamberlain, is the definitive source of rifle, pistol and shotgun ammunition performance. He’s spent well over 7,500 years working diligently with his slide rule to develop and categorize cartridge performance numbers including, but not limited to, velocity, energy, momentum, sectional density and recoil energy. More importantly, he’s sorted and categorized that data in a myriad of ways so you can easily evaluate comparative data of a near-infinite number of cartridges. Want to find a caliber that has over 1,000 foot-pounds of energy at 200 yards? No worries, that’s the kind of information you can find in the Cartridge Comparison Guide.

Anyway, my copy of the Cartridge Comparison Guide did not yet have .450 SMC data, so I emailed Andrew, knowing that he surely had done the work on it already. Fortunately, he had, and here’s how it stacks up the similar .45 ACP cartridges. Remember, these figures apply to a standard 5-inch barrel .45 ACP pistol, assuming it’s +P rated, so you can obtain improved performance with a simple ammunition swap.

Load Velocity Energy (ft-lbs) Momentum (lbs-ft/sec) Recoil Energy (ft-lbs) 160gr. Barnes TAC-XP 1,350 648 33 9.95 185gr. Bonded Defense® JHP 1,350 749 36 13.1 230gr. Bonded Defense® JHP 1,130 652 37 12.7 255gr. SWC Hardcast 1,030 601 38 12.9

As a comparison, a “standard” .45 ACP fired from the same gun calculates as follows:

Load Velocity Energy (ft-lbs) Momentum (lbs-ft/sec) Recoil Energy (ft-lbs) 230 grain .45 ACP (standard) 900 413 29.6 7.25

Recoil

In addition to myself, I asked two other shooters to test all five loads to offer their subjective opinion on felt recoil. All of us agreed that the super fast 160 grain Barnes TAC-XP load felt pretty much the same as a normal .45 ACP defensive round. The 185 grain loads were mildly stout to all of us. Where things started to get interesting was with the 230 grain loads. Those will wake you up in the morning but are perfectly manageable. The 255 grain loads get the attention of your range neighbors, three states away. I took some video of the other shooters, and when slowed down, you can see some healthy muzzle flip, but again, not uncontrollable.

The Cartridge Comparison Guide table above will give you a mathematical representation of difference in recoil energy, but felt recoil is just something you have to try yourself. Every shooter has different tolerance and ability to control the gun.

Practical Considerations

I’ve been testing all of the Doubletap Ammunition .450 SMC loads in my Springfield Armory 1911 TRP. Mine has an 18.5 pound recoil spring in it at the moment, and for occasional .450 SMC use, it’s working fine. If I decide to feed it a steady diet of .450 SMC, I’ll likely switch out the recoil spring to a 22 pound version to reduce wear and tear on the slide and frame.

For defensive use, I would not hesitate to use the 160 grain, and possibly 185 grain loads as I was confident in my ability to shoot fast and accurate followup shots. Again, speaking for myself, I would also not hesitate to use the 230 and 255 grain loads for hunting with a 1911. The 255 grain hard cast makes a heck of a hog round, especially when fired from an extended barrel 1911. Using a 6-inch barrel will give you another 100 feet per second, more or less.

If you feel the need for speed, check out the .450 SMC. Make sure your gun is up to the task, and, as with any higher powered ammo, load just one round first so you can get an idea of recoil without risk of an inadvertent second shot.

Tom McHale is the author of the Insanely Practical Guides book series that guides new and experienced shooters alike in a fun, approachable, and practical way. His books are available in print and eBook format on . You can also find him on Google+, Facebook, Twitter and Pinterest.