The S&W Model 15 revolver that remains in service, largely as a K9 training tool, can trace its lineage all the way back to the S&W .38 Military and Police Model first issued to service members back in 1899. Now, some 122 years later, this tried and true revolver is finally headed out to pasture in favor of the Defense Department’s new pistol du jour, the Sig Sauer M17 and M18 series. The last remaining Model 15 revolvers in service will likely fire their final rounds by this coming summer, ending an era.

Revolvers are a different kind of cool. The classic sixgun may never be as efficient as an automatic pistol, but it’s tough to argue that they don’t carry a certain mystique. Revolvers have had a place in national militaries for over 200 years, starting with the Colt Dragoon. They were largely phased out of service with the adoption of the M1911, but a shortage of viable service pistols during both World Wars kept these contraptions in the hands of GI’s throughout. Believe it or not, the military has kept a single revolver in its arsenal until, well, very recently.

The Air Force’s Model 15 revolver has served honorably since 1956, and the gun can trace its lineage back to 1899.

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The History of the Model 15

Let’s go back in time, and I mean, let’s start at the M15 and walk backward with it. The M15 was originally known as the K-38 Combat Masterpiece. In fact, the gun wore the K-38 moniker when it saw adoption by the Strategic Air Command Elite Guard of the United States Air Force. This wasn’t an Air Force wide purchase, but for a specific unit who apparently liked a revolver more than the M1911, the K-38 became their piece of preference. I can’t find clear evidence of why, but my assumption would be that the Air Force was likely having a tough time getting M1911s in a post-WW2 and Korean War world.

Why a Revolver?

Smith and Wesson had the K-38 as a COTS, or commercial off the shelf, product. While specialized hardware is great for the warfighter, COTS makes adoption easy. The K-38 gained its name from the medium frame that S&W designated as a K frame, and 38, which stood for the .38 Special caliber round it used. The K-38 then became the M15 when Smith and Wesson moved to number designations entirely.

Let’s keep walking back further. The K-38 Combat Masterpiece descended from the K-38 Target Masterpiece by trimming the barrel and changing the front sight. The K-38 Target Masterpiece became the Model 14, but it’s directly descended from the Smith and Wesson Model 10. The Target Masterpiece added a long six-inch barrel, a slight rib for a level sight plane, a Patridge front sight and a micrometer adjustable rear sight, with a short-throw hammer and an adjustable trigger.

Roots in World War II

The K-38 Target Masterpiece’s legacy comes from the famed Model 10. The Model 10 is the classic .38 Special revolver. This six-shot, double-action / single-action design utilized a swing open cylinder and an exposed hammer. The Model 10 premiered after World War 2 and descended from the Victory Model.

The Victory Model by Smith and Wesson was produced from 1942 to 1944. The serial numbers had a V prefix. After a half million of these guns were produced and distributed under lend/lease programs during World War 2. Another 350,000 were produced for use by the United States during WW2.

A really long name

Before the V prefix and the Victory model designation, we had the S&W .38 Military and Police Model. The M&P 38 Special traces its lineage all the way back to 1899. The Army and Navy ordered three thousand S&W .38 Hand Ejector Models that year, chambered in .38 Long Colt. Smith and Wesson cashed in on some easy marketing after this order and renamed the pistol to the Military and Police model.

The 38 Long Colt tended to be anemic, so S&W developed the .38 S&W Special, aka the .38 Special. Over time the Military and Police model had various changes and improvements. So, the famed Model 15 that is still in some armories today descended directly from a revolver that was first fielded in 1899.

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Why the Model 15 revolved has stuck around so long

It worked, and Air Force security forces acted as police officers and worked in rather safe areas. The old M15 revolvers worked well, and they stuck around long after the adoption of the M1911. The M15 served with the U.S. Air Force police from 1962 up until 1992, when the Beretta M9 saw widespread adoption.

1992 is a long way from 2021, however, so why is it still in Air Force Armories? Well, it ties back to the Air Force’s Military Working Dog training program. This program trains K9s and the M15s are used with blanks to accustom the dogs to the sound of gunfire. There Beretta pistols did not have a blank firing adapter, and revolvers simply didn’t need them.

The M15 revolver was an easy choice and a smart financial one. Why replace what works? Well, since these guns have been issued longer than my Dad’s been alive, they are likely getting worn out. Even this long-serving revolver will eventually stop training K9s and have to go the way of Old Yeller itself.

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What’s Replacing the Model 15?

The SIG M17 and M18 series will replace or are in the process of replacing the M15 revolvers across the Air Force. Unlike the M9, these guns will have a blank firing system and will cycle blanks for training purposes. The adoption of the SIG M17 and M18 series will not be complete until August 2022. I doubt there is a huge rush to arm the K9 school, so it’s likely some Model 15s are still in use, or at least still in armories, and may be well into the coming year.

It’s fascinating that the Model 15 stuck around so long and that the design traces its lineage back to the service revolvers of 1899. Has anyone in the comments ever handle an M15 in service? Let us know what you think about it.

This article first appeared at Sandboxx.

Image: Reuters.