I can see why a 4" came about -- cops and patrol cars -- but how did 6" become the default standard for DA guns?

1860s and 1851s: how long again...? 7 1/2? 8?

1873: 7 1/2 was common before it became Not Uncommon.

[Big Gap In My Knowledge Of DA/Swing Out Development Goes Here]

When did 6-6 1/2 become the norm, and normal for what? Hunting? Lots of cops carried 6" BITD, especially motorcyle cops. Plenty of room to let it hang out there.

Were the advantages of longer sight plane and velocity boost real drivers, or did it just sort of happen? I have to admit the 27's 5" barrel seems like a Goldilocks moment to me: juuuuuuust riiiiiiight. Pity it didn't metasticize to the 29 and 57.

It's on my mind because I've been lugging a 6" 29 around, only it's not as tedious as the gun culture has implied it would be by its emphasis on 4" and shorter barrels. (I concede the virtues of short barrels, but you also give something up for comfort.) I can sit with it, move comfortably... It's not quick to clear leather, I'll say that, but all in all it's fairly pleasant so far.

I have a 4" 29 on the way; I'll have to run them head to head to see if any advantage in shooting balances a perceived disadvantage in carrying.

I've always been able to shoot a 2" Model 10 as well as or better than the 4" so there is really no advantage, for me, to carry the larger gun.

__________________
Old Cop
LEO (Ret.)

It is easy to wonder why a carpenters hammer is the size it is. Or the nail the size it is. I finally assumed it was because Douglas Fir pine trees grew fast and straight and were really good for building houses. Everything else depended on working with that wood (my best guess).

Or snow shovels shaped the way they are.

With polymer show shovels I have concluded they must all fit inside each other in the box to keep the box as small as possible and thereby keep shipping charges down.

All that I know about revolvers is that the old long barrel revolvers in black powder days were heavy. Basically they replaced sabers eventually. Cross draw like a saber and cross shoulder strap to hold them up.

As metals and powder got better and eventually Calvary on horseback were replaced by army and police in Model T Fords the sitting position changed from what it was on horseback. Suddenly it was logical for police to have 6 inch barrels on strong hand side, strapped to leg, with holsters that had large swivels.

After WWII and the airplane pilots jackets caught on with the army, they became “Ike Jackets” named after general/president Eisenhower. Jacket ended at waist and equipment including military 1911 45 was on waist belt.

Eventually someone realized that a 4 inch 38 special could be holstered at the waist in a high rise holster also, like military 45’s. And it could then be drawn from the holster when inside a car. Just like military officers and their drivers could do in jeeps.

Maybe ex-military joined police departments. And too many pistols were falling out of the mechanical “clamshell” holsters. Even kids learned that you could push the little button inside the trigger guard and the holster would flip open and the revolver would fall to the floor.

This is just a 4 inch, but it is the old style "swivel holster".
Vtg Leather Police Military RH Swivel Holster Gun Pistol Revolver Cartridge Belt | eBay

(I don’t know - I’m just guessing on most of this stuff).

I find 4" revolvers balance the best for me personally. A heavy barreled model 10,13, 64, or 65 have some of the best balance of any pistol I have ever fired. I have had 6" revolvers such as 586's and 686's. I find them front heavy.

Once upon a time front heavy was good. In my first (1960’s) Prison Pistol training the subject was typical for the old old days - based on dueling pistols - parlor pistols and such. Standard issue was modern 4” model 10’s but shooting methods had not changed.

The instructor always began with “forget the cowboy stuff you see on television”. If you want to hit something with a revolver you turn mostly sideways, put left hand relaxed at your side or in your pocket, extend your right hand, cock the hammer, focus on sights - and focus on keeping a small wobble circle.

Now in this small wobble circle - as the front sight moves across the bulls eye tighten up on the trigger slightly. As it moves off the bulls eye hold - as it moves across the bulls eye again tighten a little more. When it goes off you should be surprised.

Then in about 1970 FBI statistics revealed that policemen were being lost inside 7 yards. Suddenly we shifted to the other radical extreme of drawing the gun and emptying it rapidly. Eventually people were taught to fire a few and check. Because Policemen now were being lost when reloading the revolver they had fired two quickly.

The guys with the barrel heavy six inch barrel noticed the tight group when rapid firing. But if they missed with first shot they missed with all six. The tight group often right beside what you were shooting at. After dark hesitating slightly to focus on front sight did not work well.

So the six inch barrel had more velocity and therefore more energy, and was best for target shooting. But shot lower scores in the new Hogans Alley shoot. A bigger pattern actually got more hits? You no longer missed with all six in a tight group beside your target?

No one could predict what would be next. The 1911 45acp was the answer for some. But who needed a heavy steel semi-auto that knocked them down and planted flowers.
That was harder and more expensive to reload. That was typically carried cocked with leather strap under the hammer, over the firing pin. People would stare at it wondering if it was safe. It’s reputation was too large for small towns.

What would be next. Maybe they would let us use hollow point bullets like the criminals use. No, too expensive. If only someone would make a semi-auto that the cartridge could be crimped. A hand loaders dream come true. Maybe that would be the next step? Dream on….

No one would imagine that our border patrol would be outlawed from shooting fleeing border crossers and the drug traffic would increase so much that the big death rate would become drug user overdoses and gang wars over sales turf. And drunk drivers kill more people than wars? Drugs and alcohol ruin marriages and cause wife and child abuse, and husband abuse. Broken families are now the norm.... Domestic fights the biggest police problem? Need armed psychiatrists patrolling the streets at night, responding to radio calls for help.

Why does Smith make an 8 3/8 in. barrel but Colt made an 8 in. and Ruger a 7 1/2? Some designer at the factory decided that they would offer these "standard" barrel lengths. 4, 5, 6, 6 1/2, 7, 8, or 8 3/8 who knows why for sure but these are what the factory decided would be the standard lengths. Some I'm sure were done at the request of a certain group of users, ie: LEO in a car would be more comfortable with a 4 in., concealed more comfortable with 1 7/8, 2 or 2 1/2 in., hunting some thing longer. Personally I like 6 in. but I'll carry 4 in.

Being an old coot.................

The long barrels of old were due to black powder needing long barrels to burn more completely and produce decent velocity. Hence the really long barrels on various pistols including the Walker Colts. In fact, up to the 1860s, serious pistols were referred to as horse pistols and the holsters made to fit on the saddle. When serious sidearms started to downsize, the barrels didn't change much, the most common military carrry method being setup for a draw by the opposite hand (even after many quit bothering with sabers-leading to the label cavalry draw for the twisting motion of the draw with the same side hand).

You didn't see shorter barrels on many pistols until cartridge revolvers became standard. A long sight radius was preferred by many. When reliable smokeless powder came along, barrel length became much less important so far as production of power is concerrned. BTW, black powder loads continued well into the 20th century in some calibers.

At one time many factories offered custom orders on barrel length as well as other features. If you look around on the web you can probably find a copy of Bat Mastersons order to Colt on saloon stationary for a custom built revolver (4 5/8 barrel, higher & thicker front sight, lighter trigger pull & silver plating). He definately wasn't the only person to do so. As to how the exact barrel lengths were developed? Probably what sold well in the past.

WHY?

Because after months of research and years of study the folks manufacturing the handguns figured what barrels were useful for what purposes and how much money people would pay for what they wanted.

Thanks Mr. Moore. You're the first person to address the actual topic. : )

6" is obviously a tradeoff between portability and best possible function; i.e., most efficient burning of powder. But the 6" has been around as long as cars have, so it wasn't really a saddle gun -- it was meant to be carried as a sidearm. Civilians find it hard to hide them, so it's not popular as a concealed length, and most cops have gone to autoloaders. And yet they still make them, and not just in stainless for hunters.

They are pointable, balanced asmuch as they need to be -- a little fornt heavy, but with most calibers the big N comes in, that's good for muzzle control.

Would love to have a 5" 29-2. Would even love to SEE one. They were never made, right...?

All the way up till about 1990 in Sn Diego CA the police issued 6" skinny BBL m-10's The cops could buy different, but the issue was the 6". Why? I don't know.

Tradition?

Up until about 1970 I think most police departments were target shooters. And with the old lead bullet you probably got an extra 80 or 90 feet per second (lead has less resistance going down the barrel). My old Speer Manual number 9 gives the upper 158 grain lead bullet load for 6 inch barrel 38 special traveling 1250 feet per second. Most 158 grain lead bullet loads were in the 1100 feet per second speed. (With a much heavier bullet than 9mm).

After 1935 the .357 magnum was available but considered to powerful for cities. And too expensive to replace all the other revolvers bought in bulk numbers. No city council thinks guns are a good way to spend money. Just a necessity.

In the old old days you read about some marshal or sheriff hitting someone with the barrel of his pistol. You never heard of Marshal Virgil Earp or Wild Bill Hickok carrying a nightstick. When Marshall Virgil Earp was told that Ike Clanton had been drinking all night and bragging that he was going to shoot the marshal from a alley when he did his morning rounds, that was serious. Virgil checked the alleys from the back side, walked up behind Ike laying behind boxes with a rifle, said something like “looking for me Ike”. When he turned fast he hit him with the barrel of his revolver. As reported in the Tombstone newspaper and later written in Time Lifes old west books. I believe that one was “The Gunfighters” and can still be bought on line.

At some point nightsticks became police issue. More recently mace/pepper spray and stun guns & tasers. You do not hear the word “pistol whipped” much anymore.