The Colt Officer's Model series were the top formal Target revolver in the days before the automatics took over.
Back then, the Colt's held all the records and the top shooters used the Officer's Models and the large frame New Service Shooting Master.
Top shooters often had their guns modified by companies like King's, who offered various hammer modifications and sights.
Colt offered special order guns with single action-only conversions.
Many were owner modified to SA-only by removing the double action strut from the hammer.
The Colt factory SA-only conversion also converted the Colt long action to a short action with a shorter hammer fall.
The Officer's Model as made from 1908 to 1969 will often shoot with a Python for accuracy as long as it's in good condition and in proper adjustment.
The pre-war Officer's and Shooting Master were Colt's top of the line revolvers and were until the super-premium Python was invented. The Python was originally going to be a .38 Special Super Target revolver until Colt decided it would sell better in .357 Magnum.
The pre-war Target Colt's made during the 1930's when gun making was at it's quality peak are extremely high quality.
They featured checkered hammer, cylinder latch, (so you could rest your thumb on it) trigger, front strap, and back strap.
Front sights were adjustable for elevation, rear sight for windage.
Post-war the short production Officer's Model Special had an extremely heavy bull barrel and the limited time used Coltmaster fully adjustable rear sight.
The post-war Officer's Model Match had the Colt Accro fully adjustable rear sight and the first use of Colt's famous long Target hammer and Target grips.
On special order the Colt Ellison Target rear was available and as an owner replacement the Colt Ellison Target rear sight will drop in.
New Ellison's are sold by Kensights:
Kensight Sights Stop-By to Compare the Best Sight Reviews
As for fragile actions, the Colt action won't take the kind of abuse you can get away with on the S&W and Ruger revolvers, but then, you can't abuse a Ferrari like you can a pickup truck either.
As said, when the trigger is held back the cylinder should lock up tight. This is not a valid test for any other DA revolver like the S&W, Ruger, or later Colt's like the Mark III.
The major source of the "fragile" Colt action story is the hand that rotates the cylinder.
When the trigger is pulled the cylinder is forced by the hand into tight lock up and that causes eventual wear of the hand.
In the original Colt action the hand is a standard maintenance item that when worn needed to be either re-fitted or replaced.
The problem is that many current shooters don't know the gun needs maintenance and continue using it, often doing damage.
This is rather like driving the Ferrari long after it's due for new plugs.
Fortunately Jack First Gun Parts is manufacturing key Colt parts like the hand and bolt.
You still have to find a genuine Colt expert to work on them, but there are still a few around, like Frank Glenn in Arizona.
The Colt action is a complicated, difficult action to work on, but if you don't abuse it it'll last for a long time, especially if used as a single action Target revolver.
If you'd like a superb quality revolver with Python level accuracy the Officer's Models and Shooting Master can't be beaten.
Here's how to inspect a Colt original type action as used up until the Python. This is not valid for the later Colt's like the Mark III and later.
To check Colt timing:
BOLT RETRACTION AND "SNAP BACK".
Open the cylinder and look at the small "lug" in the bottom of the cylinder window. This is the cylinder locking bolt.
Cock the hammer, and watch as the bolt retracts into the frame and pops back out.
The bolt MUST begin to retract THE INSTANT the hammer begins to move.
There MUST be NO (ZERO) hammer movement possible before the bolt starts to retract.
The bolt should retract smoothly with no hesitation until it's fully retracted, then it must pop back out with a clean "snap".
There should be no hesitation, and no amount of "creeping" back out.
CYLINDER UNLOCKING.
Close the cylinder.
Use your left thumb or fore finger to again cock the hammer, closely watching the cylinder bolt as you SLOWLY cock the hammer.
As the hammer comes back, the bolt will retract away from the cylinder.
The bolt must retract far enough to unlock the cylinder BEFORE the cylinder begins to rotate.
If the bolt is still slightly engaged with the cylinder lock notch, the cylinder will be attempting to turn while still partially locked.
This produces a "catch" or "hard spot" in the trigger pull and will damage both the bolt and the cylinder lock notches.
This often appears as metal "pulled out" of the lock notches, with rounded off and burred notches.
BOLT DROP TIMING.
Continue to cock the hammer, LIGHTLY laying your right index finger on the cylinder just enough to prevent "free wheeling".
Watch for the bolt to drop back onto the cylinder. WHERE the bolt drops is CRITICAL.
The bolt MUST drop onto the leade or ramp in front of the actual cylinder notch.
If the bolt drops too soon, (in front of the notch ramp), it will mar the finish of the cylinder.
The bolt should drop into “about” the middle of the ramp.
If the bolt drops late, (farther toward the actual locking notch) the revolver may display "cylinder throw-by".
In this condition, during double action shooting the cylinder may rotate PAST the locking notch, and fire in an unlocked condition.
It's the nature of the Colt action, that a hesitant or jerky trigger pull by the user can induce throw-by in even a properly tuned Colt.
The Colt trigger should be pulled with a smooth, even pull, with no sudden jerks at the beginning.
CYLINDER LOCKUP.
Continue to pull the hammer back and both watch and listen for the bolt to drop into the cylinder lock notch.
The bolt must drop into the actual lock notch before or just as the hammer reaches full cock.
The most common Colt mis-time situation is the hammer cocks before the bolt drops into the lock notch. (Hammer is cocked, but cylinder isn't locked).
In this condition, with the hammer fully cocked, you can push the cylinder slightly, and you will hear the "CLICK" as the bolt drops into lock.
In my experience, most Colt's leave the factory with the bolt dropping a little late into the leade, but usually wear in to correct timing.
If the bolt drops onto the cylinder early, no real problem, but there will be extra finish wear.
If the bolt drops late (closer to the lock notch) the cylinder may "throw by" or rotate TOO far in double action and this can cause off-center primer hits and firing while unlocked.
Each of these checks should be done on EACH chamber. All of these checks are better done individually. In other words, do the bolt retraction check on all six chambers, then do the bolt drop test, and so on.
A properly tuned Colt will:
Have a smoothly functioning bolt with no sticky or hesitant movement.
Unlock before the cylinder begins to turn.
The bolt will drop onto the middle of the ramp.
The bolt will drop into the lock notch just before or as the hammer reaches full cock.
Have a smooth trigger pull, which does "stack" or get heavier as the trigger is pulled.