Mainspring on '52 Colt Official Police

S

Sevens

New member
Got a buddy that is, for all intents and purpose, not really a "gun guy." We've got an event that we go to every year at a friends cabin in the mountains and this friend of mine always brings the one revolver he owns and it gets it's annual 50 rounds. All well and good, he's a great guy and a long time friend, he's just not a serious gun guy. The revolver is a Colt Official Police, .38 Special with a 6-inch barrel and the serial number dates it to 1952. He bought this gun from a neighbor who had a garage sale, he's probably had it 5 or so years... IIRC, he paid around $125 for it. It's a beautiful revolver.

These days, it eats my handloads and enjoys them, however I use CCI small pistol primers exclusively and as many will recognize... there is no harder-cup non-magnum primer on the market. So if a revolver has any tendency to FTF on a double action trigger pull, the CCI-500 primers will expose that tendency.

And this is what happens with this revolver, usually to the tune of 1 or 2 each cylinder. They always fire with a second attempt, and always fire with a single action cock & execution.

I see that I can buy an aftermarket mainspring for this at Numrich:
http://www.gunpartscorp.com/Products/1365010B.htm
...it's a bit over twenty bucks.

The Question!
Is this an easy, slip in part? I don't see a strain screw to take pressure off the spring like a Smith & Wesson has... so if swapping out this main spring involves tearing in to the revolver, I'm all but certain that he'll be uninterested in bothering with it at all.

I'm far from a gunsmith. I shouldn't even be allowed to use the word gunsmith. I do a fine job at caring for handguns and addressing very minor issues, but I have NO BUSINESS taking apart a 1952 Colt revolver.

So please, tell me how much is involved with swapping out a main spring on this nice old shooter.
 
You realize that a stronger spring will make it harder to shoot, double action.
For someone who rarely even shoots, it's more than mildly probable that he will wind up shooting it single action with a heavier main spring.
Which is what he's kind of doing anyway.
And, if he starts buying his own factory ammo, he'll be better off with the stock one.
Might be better to leave it as it is.
Pretty sure that to change the mainspring, the side plate has to be removed.
With the chance of strange parts falling out.
If you decide to go ahead, look at some youtube videos on how to do it.
 
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Are you sure that you're getting your primers seated properly?

What you're describing, FTF first strike, fires second time around, really sounds like primers that are just a little bit shallow. The first strike finishes seating the primer, the second strike fires it.

Have you ever had a Colt revolver apart before?

They are nothing like a Smith & Wesson. I taught myself how to disassemble an S&W, so I figured a Colt would be equally accessible.

I removed the grips and sideplate from the Detective Special I used to own, studied it for awhile, and then very gently put it back together when I realized that I was in over my head.
 
I know that he is the type that would rather own a revolver in perfect working condition, even if it meant a hard trigger pull. I'm quite familiar with how a double action revolver works and yes, I'd be expecting a heavier DA pull.

I'm also long time and very high volume handloader and the 850 other rounds of center fire expended last weekend across seven different chamberings were 100% in feed, firing, function and on-target performance. "Never say never" but I can safely and honestly rule out substandard handloading as the problem here. In fact -- handloading with the CCI-500 is likely the biggest reason we saw FTFs in double action from this fine old revolver.
Pretty sure that to change the mainspring, the side plate has to be removed.
With the chance of strange parts falling out.
Click to expand...
-and-
I removed the grips and sideplate from the Detective Special I used to own, studied it for awhile, and then very gently put it back together when I realized that I was in over my head.
Click to expand...
Exactly why I started the thread. If I can't swap out the mainspring without taking a side plate off this revolver, this job is not going to be attempted. I know enough to stay away when I should, which is a skill that I'm proud of at this point! ;)

For sure, this revolver isn't "broken" and if a spring swap isn't a quick & easy little job, it's just not going to be goofed with.
 
I would leave it alone if I were you, and if he only shoots it once a year, buy a box of factory ammo once a year for it.
 
Mike Irwin gave you good advice, make sure that the primers are seated below the face of the cartage (should be a few thousands of an inch). I know from experience this can cause problems with CCI primers. If it works OK with factory ammo, Colts are not for the novice to work on. :)
 
While we wait for Dfariswheel to log in, I will state in the older Colt action-I don't think anything is a drop-in part. And yes, when in doubt-don't.
I am working on an old Colt Police Positive with the aide of Kuhnhausen's and some other references, the first rule on working on an older Colt is:
1. You read the directions and instructions
2. Then you read them again.
3. And again.
Then you proceed methodically step by step, watching carefully to see how the action works and the parts fit together.
 
With the Kuhnhausen shop manual and two Brownell's Magna-Tip screwdriver bits you can change or repair the mainspring.

In some cases you can repair the original spring, because the "usual" in these cases is that someone attempted to lighten the trigger pull by bending the spring.
This is done by inserting a piece of drill rod between the "legs" of the spring and cocking the hammer. This puts a bend in the upper leg of the spring.
This IS a valid technique, but most people don't use a trigger spring gage to insure they don't lighten it too much and over do it.
Result is misfires, usually in DA.

In many cases, you can use smooth jaw or padded needle nose pliers to unbend the top leg of the spring and this may well restore proper function.
The place to bend is in the middle of the top leg, and you may be able to see where it was bent.

The Kuhnhausen shop manual was written as a training aid for new gunsmiths and shows all factory type repairs in depth, including full disassembly and reassembly the right way.
Use the manual to remove the side plate and the spring.

For screwdrivers you'll need two bits for a Colt medium frame like the Official Police, one to fit the cylinder retention screw and one to fit the side plate screws.
You'll need a Magna-Tip number .210-4 for the retention screw, and a .150-4 for the side plate screws.

With the manual and the driver bits replacement or repair of the mainspring is not a complicated job.

http://www.brownells.com/books-vide...action-revolvers-a-shop-manual-prod25720.aspx

http://www.brownells.com/gunsmith-t...ewdrivers-sets/magna-tip-bits/index.htm?f_a=1
 
Try also Jack First and Colt Parts (not part of Colt firearms) for a "v" spring. It's the same spring as the one used by the Python.
 
Yes, you can replace a Colt mainspring without removing the sideplate, if you know exactly what you have to do, and that is not easy to explain on here.

And, as others have said, the trick is not taking off the sideplate, it is getting it back on without having something get out of place.

Here is a way you might be able to increase that spring tension: Remove the grips. With the gun right side down, barrel to the left, you will see the mainspring, a long V shaped part. If you will see the V close and the open as the hammer is cocked and released. Try inserting a small piece of wood, like a piece of toothpick, into the small part of the V. Cock the hammer again, and try the DA pull. If things are OK and the piece of wood stays there, put the grips back on.

Jim
 
Great information, gentlemen. Much appreciated.

If the revolver were mine, I'd be likely to go inside. Alas... it is not.

I hope to try the trick with the piece of wood, but there's simply not enough reason to go inside this old revolver.

Here's a side nugget: On the butt of this one, where Smith & Wesson puts a serial number, this Colt doesn't have a serial number -- however, in some manner of a fancy kind of script, it does say "No. 127" in a fairly large font. (Which is to say, larger than S&W would engrave a serial number... just for reference)

There are no other markings or stampings on this revolver to indicate the former property of some issuing agency. But would it be a safe assumption or guess that the engraved "No. 127" might have been a catalog number of some such agency?
 
You know, thinking about this some more, the answer might be a LOT more simple...

When was the last time the gun was given a THOROUGH internal cleaning and lubrication?

Reading through your posts on how it's been used in the past, I'm going to venture a guess and say pretty close to never...
 
I'd have to agree. But unless a Colt revolver is wildly different than a Smith & Wesson, I'm one of those folks who would never consider shooting anything in to the guts of a fine double action revolver unless & until something else has warranted such an extreme action.

My 1921 Fourth Change has definitely had nothing sprayed in it since 1923.
My 19-3 hasn't seen anything of that manner and it was born in '73.
My Models 17 & 686 are of '88 and '89 vintage respectively, and neither have seen a drop of anything inside the lockwork nor even been cracked open.

I just wouldn't do that. FAR from an expert, but this tactic has worked incredibly well on my Smith & Wesson revolvers.
 
"I'm one of those folks who would never consider shooting anything in to the guts of a fine double action revolver"

Gun Scrubber is hardly an extreme action.

When you're dealing with a Colt, the FAR more extreme action is taking the damned thing apart.



"My Models 17 & 686 are of '88 and '89 vintage respectively, and neither have seen a drop of anything inside the lockwork nor even been cracked open."

Wow.

I don't even want to know how you deal with you car! :eek:
 
Hmmm, same way I deal with my motorcycles...
But my revolvers sure run phenomenally well.

Not trying to be adversarial, even a tiny little bit -- I'd love it if you could handle each of the three I mentioned. Perfect timing, absolutely smooth mechanics. None of the three have double action trigger pulls that hint or appear to have undergone some quality trigger job... however each of them runs like a (hmmm, well-oiled) machine! :p

No, really. I can't imagine spraying anything inside any of the three of them if there wasn't some genuine cause to make me do so.

To clarify, I have done this before, when warranted. On a Colt King Cobra that had something "sticky" going on inside, I did many go-rounds with carb cleaner to work out the GUNK that was sticking things up. My best guess on this gun who's history I don't know is that someone sprayed something in there a decade or two before I got it.

Some crap congeals and does bad things. Some stuff does not. I don't have it all hashed out. But in a quarter century with a couple of these... my experience has told me that when you don't squirt ANYTHING in there, there's nothing to congeal or otherwise go goofy.

I don't attempt to make any claims or bold statements about what "SHOULD" be done, but I can sure tell you what has worked on three revolvers that I am 100% positive have never had anything outside of the factory squirted in to them.
 
The numbers on the butt are usually stock numbers for a private company guard service, security company, or police department.

This Colt will have it's serial number stamped on the frame below the barrel where the cylinder crane seats, also on the cylinder crane, and often inside the side plate.
 
It all depends on what is sprayed in the gun.
Soak in mineral spirits, clean with brush, swish in mineral spirits, spray thoroughly inside and out with brake cleaner.
No residue, and squeaky clean.
Then lube and wipe down with slightly oily cloth.
Careful on some plastics, though.
Even mild solvents can melt and discolor some of them.
 
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