Colt Helped Save It. Kimber Took It to the Next Level.

There are cartridges I enjoy shooting. There are cartridges I respect for what they can do.

And then there is the 10mm Auto.

I’m a 10mm superfan and I make no apologies for it.

Velocity. Energy. Accuracy. Versatility. History. And just enough attitude to remind you when the hammer falls that you’re shooting something a little different.

Few semi-automatic handgun cartridges have this much personality.

The 10mm can be loaded for an enjoyable afternoon punching paper or pushed into an entirely different performance category with ammunition designed for hunting and other demanding applications.

But perhaps the greatest part of the 10mm story isn’t what it can do.

It’s that the 10mm probably shouldn’t still be here.

It has been called too powerful, too much recoil, too expensive, unnecessary and obsolete.

It watched its own offspring become one of America’s dominant law enforcement cartridges.

It survived the demise of the pistol originally built around it.

And yet here we are.

More than four decades later, the 10mm isn’t merely surviving.

It’s thriving.

And now we’re putting it into double-stack 1911s.

What a time to be a 10mm fan.

It Started With a Vision

Every 10mm enthusiast owes a debt of gratitude to Jeff Cooper, Thomas Dornaus and Michael Dixon.

The concept was ambitious: combine serious ballistic performance with the advantages of a semi-automatic pistol.

The Bren Ten became the handgun most famously associated with that vision made iconic by the 1980’s tv show Miami Vice.

Unfortunately, the Bren Ten’s story was short.

The pistol disappeared.

The company disappeared.

But somehow the cartridge refused to go with them.

That wouldn’t be the last time the 10mm survived something that probably should have killed it.

Then Came the FBI

The 10mm eventually attracted the attention of the FBI following the infamous 1986 Miami shootout and the Bureau’s subsequent search for improved handgun ammunition performance.

The cartridge certainly had horsepower.

Ultimately, however, reduced velocity 10mm ammunition demonstrated that the performance the Bureau wanted could be achieved without using the cartridge’s full potential.

Which raised an obvious question:

If we’re not going to use the whole case, why do we need the whole case?

Enter the .40 S&W.

The shorter cartridge could deliver similar performance to reduced-power 10mm loads while fitting into smaller handgun platforms.

The .40 S&W exploded in popularity.

The 10mm didn’t.

For a while, it looked like the child might actually kill its parent.

But the 10mm wasn’t finished.

Not even close.

Colt Throws the 10mm a Lifeline

This is where the Colt Delta Elite earns a very special place in this story and in my collection.

After the Bren Ten disappeared, Colt put the 10mm into one of America’s most recognizable handgun designs:

The 1911.

To me, the Delta Elite wasn’t simply another pistol chambered in 10mm.

Colt helped keep the 10mm alive.

It gave shooters a major production handgun chambered for the cartridge and helped keep 10mm ammunition, brass, handloading data and enthusiasm alive through years when much of the mainstream shooting world had moved on.

Had Colt not taken that chance, would the 10mm have survived long enough to enjoy what we’re experiencing today?

Maybe.

But I’m glad we never had to find out.

That’s why I’ll always consider the Colt Delta Elite one of the heroes of the 10mm story.

Cooper, Dornaus and Dixon gave us the vision.

Colt helped keep the flame burning.

Eventually, that flame became a fire again.

2018: Something Was Happening

I originally published my 10MM Loading Depot article on September 9, 2018.

At the time, something was clearly changing.

New 10mm pistols were appearing.

Ammunition manufacturers were paying attention.

Hunters were paying attention.

And handloaders?

Some of us had never stopped paying attention.

Shooters were rediscovering what 10mm fans had been saying for years:

The 10mm Auto is one heck of a handgun cartridge.

In that original article I asked:

Are 10mm fans finally getting the respect and support they deserve?

Eight years later, I don’t think there’s much question about the answer.

Yes.

In fact, I think we’ve moved beyond the comeback.

We’re living in something approaching a golden age of the 10mm.

Why I Love the 10mm

One word:

Options.

Want something enjoyable for an afternoon at the range?

The 10mm can do it.

Want serious full-power factory ammunition?

It’s available.

Want to handload and explore different bullet weights and applications while staying within published data?

Few semi-auto cartridges are more interesting.

Want a traditional single-stack 1911?

Absolutely.

Want a modern double-stack?

Welcome to 2026.

That enormous performance envelope is one of the reasons I’ve remained fascinated with this cartridge for so long.

The Magnum Comparison

People have compared the 10mm to the .357 Magnum for decades, and there’s good reason.

Depending upon barrel length, bullet weight and ammunition, their performance envelopes can overlap considerably.

Yet the 10mm provides that performance from a semi-automatic platform with the capacity and reload advantages that come with it.

You’ll even hear comparisons with the .41 Magnum.

That comparison deserves context. The upper end of .41 Magnum revolver performance isn’t something we should casually claim the 10mm duplicates.

But think about the company we’re keeping.

We’re discussing a rimless semi-automatic pistol cartridge alongside two legendary Magnum revolver cartridges.

That alone tells you something about the 10mm.

But the 1911 Had a Problem…

Now we get to one of my favorite parts of this story.

If you’ve spent any amount of time around 1911 enthusiasts, you know there are certain subjects that should probably be avoided at family gatherings.

Series 70 versus Series 80.

9mm versus .45 ACP.

Full-length guide rods.

John Moses Browning versus practically everybody.

And then there’s the big one:

“BUT IT DOESN’T HOLD ENOUGH ROUNDS!”

I’m fairly certain friendships have been lost over this argument.

Maybe marriages.

Probably a couple of gun-club memberships.

For more than a century, 1911 shooters have praised the platform’s trigger, ergonomics, accuracy, shootability and history.

And critics answer:

“Yeah, but capacity.”

The 1911 guy responds:

“But the trigger…”

Capacity.

“John Moses Browning…”

Capacity.

“Two World Wars!”

CAPACITY!

Okay.

Fair enough.

How about a double-stack 1911 chambered in 10mm?

Now things get interesting.

Enter the Kimber 1911 DS Warrior 10mm

This is where I think the modern 10mm story comes full circle.

Sitting next to my Colt Delta Elite today is something that represents an entirely different period in the life of the cartridge:

The Kimber 1911 DS Warrior in 10mm Auto.

My pistol is Kimber Product #3600303, UPC 669278363035.

It’s a full-size, 5-inch, optics-ready, double-stack 10mm 1911.

And then we get to the fun part:

15- and 18-round magazines.

Read that again.

Eighteen rounds of 10mm.

In a 1911-style pistol.

Put the 18-round magazine in the pistol and add one in the chamber and you’re looking at:

18+1 Rounds of 10mm

Nineteen rounds.

Suddenly that old capacity argument gets a lot harder to make.

Modern Pistol Guy: “Yeah, but your 1911 doesn’t hold enough rounds.”

1911 Guy: “It does now.”

Argument adjourned.

Colt Saved It. Kimber Evolved It.

That’s why I don’t look at these two pistols simply as an old 10mm and a new 10mm.

To me, they represent two eras of the cartridge.

Colt Delta Elite — The Savior

The Delta Elite represents survival.

It came from an era when the 10mm needed champions.

Colt kept the cartridge connected to a major American manufacturer and one of the most iconic handgun platforms ever created.

Kimber DS Warrior — The Evolution

The Kimber represents something very different.

The 10mm no longer needs rescuing.

Now manufacturers get to ask:

What else can we do with it?

Kimber took the classic formula, kept the 10mm, added modern features and attacked the 1911’s biggest criticism with a double-stack magazine.

That’s evolution.

Put these two pistols beside each other and you can almost see the history of the cartridge.

The Colt represents where the 10mm has been.

The Kimber represents where the 10mm is going.

But There’s a Catch: Those Magazines

As much as I like what Kimber has done with the DS Warrior, I’m not writing an advertisement.

There’s something I don’t like.

Magazine price and availability.

The whole point of going double-stack is capacity, so naturally one of the first things I wanted was additional magazines.

That’s where things become painful.

Depending upon what you paid for your DS Warrior, one additional magazine can represent approximately 5–8% of the purchase price of the entire pistol.

Think about that.

Not an optic.

Not a barrel.

Not a trigger job.

One magazine.

That’s hard to ignore.

The Unicorn 18-Round Magazine

There’s another problem.

The 18-rounder may be the most interesting magazine for this pistol.

Unfortunately, finding another one has been a different story.

Kimber lists the 18-round magazine, but since the pistol’s release, I’ve found aftermarket availability practically nonexistent.

The magazine exists.

Finding one for sale is another matter.

My suspicion is that Kimber may be prioritizing available 18-round magazines for the pistols leaving the factory.

I want to emphasize that this is my speculation, not something Kimber has told me.

And from a manufacturing perspective, it would make sense.

But from an owner’s perspective?

It’s frustrating.

If you’re going to give me 18 rounds of 10mm, eventually I’m going to want more than one magazine capable of holding those 18 rounds.

Hopefully this is simply an early supply issue that improves as production catches up.

Then the Magazine Price Made Me Realize Something

The more I thought about the magazine price, the more something occurred to me.

If one magazine can represent 5–8% of what I paid for the entire handgun…

maybe the bigger story isn’t only that the magazine is expensive.

Maybe the pistol itself represents an unusually aggressive value.

Look at what we’re getting:

10mm Auto.

Full-size 1911-style platform.

Double-stack capacity.

Optics ready.

Up to 18 rounds in the magazine.

The double-stack 1911/2011-style market can become expensive very quickly.

Yet Kimber has managed to put together this package at a price that makes the DS Warrior potentially one of the more interesting value propositions in today’s double-stack market.

There’s an important distinction here.

I’m not calling it cheap.

Cheap and value aren’t the same thing.

I’m saying Kimber appears to have substantially lowered the price of admission to a double-stack 10mm 1911.

Ironically, the price of the magazines helps illustrate just how aggressively the pistol itself is priced.

So what’s my complaint?

Pretty simple:

Kimber, Give Us Magazines!

Preferably enough of them that availability improves and competition eventually helps bring prices down.

Because right now the DS Warrior presents an almost comical contradiction:

The pistol may be one of the better values in the double-stack game.

The magazines definitely aren’t.

Still, if my biggest complaint about an 18-round double-stack 10mm 1911 is that I want more magazines for it…

That’s probably a pretty good indication of how much I like the pistol.

With Power Comes Responsibility

My enthusiasm for the 10mm doesn’t mean ignoring what happens inside the chamber.

The 10mm operates at substantial pressure.

For handloaders, chamber dimensions, barrel design, chamber support, brass condition, component selection and published loading limits all matter.

This was one reason the Colt Delta Elite played such an important role in my original testing.

I wanted to examine ammunition performance in a classic 10mm platform while paying close attention to chamber support and fired brass.

That’s not criticism of the Delta Elite.

Quite the opposite.

Understanding the characteristics of the individual firearm you’re loading for is part of responsible handloading.

And that’s something I want the 10MM Loading Depot to continue emphasizing.

The New 10MM Loading Depot

My original goal wasn’t to find one magical handload.

I wanted to explore the cartridge’s capabilities.

And that’s still the goal but I want this page to become much bigger than the article I published in 2018.

I want the DayAtTheRange 10MM Loading Depot to become a living database.

Factory ammunition.

Handloads.

Chronograph results.

Accuracy.

Bullet weights.

Barrel lengths.

Extreme spread and standard deviation.

Single stacks.

Double stacks.

Classic pistols.

Modern pistols.

And perhaps most importantly:

What actually happens when we pull the trigger?

Because the number printed on an ammunition box is interesting.

A chronograph reading is better.

A target is better still.

Put all three together and now we’re learning something.

That’s DayAtTheRange.

A Note About Reloading Data

The original version of this article contained my personal handloading results and guidance surrounding those loads.

Eight years later, I want to make my position clearer.

My load results are test data—not load recommendations.

They document what particular combinations produced in particular firearms with the components available during my testing.

Handloaders should verify their components against current published data from reputable reloading manuals and powder/component manufacturers, begin where that data instructs them to begin, and remain within its published limits.

Components change.

Lots change.

Firearms differ.

Chambers differ.

Brass differs.

There isn’t a velocity number on Earth worth damaging a firearm or yourself — to achieve.

The purpose of the Loading Depot is to:

Measure. Compare. Document. Learn.

From Bren Ten to Delta Elite to Double Stack

This is the part of the story I couldn’t have written in 2018.

Back then I was celebrating a comeback.

Today I’m celebrating something bigger.

Evolution.

Cooper, Dornaus and Dixon helped give us the vision.

The Bren Ten introduced the concept.

The FBI helped write one of the strangest chapters in its history.

The .40 S&W nearly overshadowed its parent.

The Colt Delta Elite helped keep the 10mm alive.

Enthusiasts kept shooting it.

Handloaders kept loading it.

Ammunition manufacturers kept improving it.

Firearms manufacturers came back to it.

And now I’m sitting here looking at two pistols that tell that entire story remarkably well.

A Colt Delta Elite.

And a Kimber DS Warrior.

One represents survival.

The other represents evolution.

The 10mm Didn’t Just Survive

When I originally wrote this article in 2018, I called the 10mm one of my favorite cartridges.

Eight years later?

Nothing has changed.

Actually, that’s not true.

I probably like it even more.

The cartridge that supposedly had too much recoil survived.

The cartridge that was downloaded survived.

The cartridge whose shortened offspring nearly replaced it survived.

The cartridge that spent years being dismissed as a niche round survived.

And that old argument that the 1911 doesn’t hold enough ammunition?

Well…

18+1.

Your move.

The 10mm didn’t just survive.

It evolved.

And the DayAtTheRange 10MM Loading Depot is going to document where it goes from here.

Long live the centimeter.

Practice safe handloading, verify your data, and keep them all on target.