Been doing some reading on these after hearing about one for sale.  Apparently earlier ones may have issues with proper magnum loads?

It's a stainless, and I thought they said the barrel length was 5 3/8", but I'm not seeing that barrel length listed on the sites I've checked thus far.

All the 19s and 66s were light for much magnum use.  That's why the L frame was developed.  19/66 was for the era when you carried mag ammo but practiced (if ever) with 38.  Also, some or all of the 66s have a ring which comes loose and jams the gun, these were later better secured in place.

Magnum rounds above 125gr. won't do harm, but the heavier weight bullet the better. I have a 66-2, but only shoot a max of .38spl +P ammo in it. They're still fantastic revolvers.

I own 4 k frame magnums and have handled/ inspected many many more

there is alot of hearsay regarding the k frame magnums and even more info that is inconclusive.

I am a huge 66/19 fan hear is what I believe

supposed problems occur in 3 places.

1. cylinder lock- magnums supposedly loosen but can be checked.- I have a sheriff marked 66 that show tons and tons of use but is still very tight

2. top strap flame cutting - here is the easisest to avoid and detect. look at the top strap just above the forcing gone you should see a blast mark all revolvers show this even 22lr and n frames in 357. IMO it is mostly cosmetic and has no effect on operation.

3. forcing cone cracking. if you examine a 66 forcing cone you will find the bottom is flattened and thinned.there are 2 theories on why the cone cracks.
A. heavy lead deposits shrink the cone area causing cracks.

B. alot of super light fast magnums cause accelerated wear.

SO HOW TO AVOID WEAR ???

don't shoot 110/125 grain loads commonly in K frames if you shoot 150+ grain bullets the longer bullet causes less top strap cutting and  cone wear. keep the forcing cone clean using a lead scraper and shoot jacketed bullets to reduce lead build up.  

My favorite point hear is that a K frame is weak and has problems  but a j frame in 357 has none


revolver barrels are measured from the front of the cylinder not the back (like autos) so many mis measure  66 were offered in 3", 4" (most common) & 6" there is no 5" what you have is most likely a 4" measured wrong.  

if the price is good grab up a 66 anything under $400 if in good condition is pretty good IMO

I would imagine it is a 6" bbl measured wrong.
Not many people include the cylinder, most don't account for the barrel inside the frame.

I have had one for a number of years and have no complaints. The above mentioned problems were there, however I have carried  mine on duty and never felt "undergunned" or that I had less of a weapon. In my hands it has been one of the fastest and most accurate handgun I have ever owned. My opinion you can't go wrong.

Because revolver barrel measurements traditionally don't include the cylinder...as it's not part of the barrel the way it is in an auto-loader.

This may sound blasphemous, but for most people, the best use for a revolver is as a woods gun (hiking, camping, hunting, fishing, etc.). I the context of a woods gun, the 125 grain load that are known to crack the shaved forcing cones of the K-frame are much less desirable than a 158gr. or heavier Magnum load. When I'm out in the woods, I'm worried about creatures whose physical builds require more penetration than the modern "service" calibers provide. The 125gr .357 Mag has a great reputation as a man-stopper, but in a "woods gun" I want something with a long-standing reputation as a critter-stopper.



Down here in Florida, I've hiked my share of woods filled with various dangerous critters, and a K-frame loaded with 158gr Soft Points is ideal for the majority of situations. If I have a higher likelihood of encountering bears, then a 180gr Hard Cast load is what I choose, albeit in an L or N-frame. Of course, we only have those "small" Black Bears that are ~400 lb. give or take.



My 3-1/8" pre-lock Model 66-5 is my #1 choice when I'm in the Florida woods (yes, it's 3-1/8" and S&W can't measure worth a damn! ). The 125gr Magnums offer me nothing for my purposes.

They have addressed all of the concerns . I own an ex pd 66 , no issues and one of the nicest triggers on any gun I have ever shot

The 19/66 can shoot magnums, but the short length 110 & 125gr bullets are really hard on the forcing cone.

If you want to shoot magnum level 125's,  get a 686

I have an old model 19 and I shoot 140gr- 168gr thru it.

I shoot .38 level loads in .357 magnum cases in my model 19 (blued twin of 66).  Not that the gun won't take it, I just like target shooting with my 6"  K frame.  I sure as hell am not quick drawing it.  

that's a damn good looking gun.

Nothing wrong with a 19/66 but as stated best use 158gr magnums or like most folks use .38 special or +p ammo.  One of my all time favorite revolvers.

125gr magnum loads will crack the forcing cones in K-Frames. But saying that heavier magnum loads won't hurt them is not accurate at all.

When I turned 21 Karl Sokol at Chestnut Mountain Sports built me a custom 3" 65 for my first carry gun. I shot and carried that revolver almost exclusively for four or five years. Back then I was young and a little misguided and felt that every round I fired had to be close to max magnum loads, and just about all of them were my own handloads using a cast 158gr SWC and usually Bullseye powder.

After years of almost daily shooting and 10,000+ 158gr magnum rounds the 65 was becoming very loose and had a lot of flame cutting on the face of the cylinder and top strap. It was getting pretty rough by the end of it but the damage was there about halfway through it.

It will take a lot less 125gr loads to damage a K-Frame but 158gr loads will do it too.

the kind of shooting you describe would loosen an n frame  snd I hsve seen flame cutting on 38 spc only guns so it is unavoidable.