Cylinder end shake fix for Colt Police Positive

Pistolero

Well-Known Member
OK, intheshop asked about this and here it is. The price at a gun show with the
action locked up was $100, but I noticed the side plate was not all the way down,
figured someone had pulled it apart, couldn't get it back together and had parts
out of place, locking it up. Turned out to be correct.

Here's the story:

I bought a 5" Colt Police Positive, which is a .38 S&W gun. The price was very
low, so I figured it had to have something significantly wrong with it, but OK it
would be fun to see if I could figure it out and fix it. A close inspection prior to
purchase showed that the cylinder, chambers, barrel and frame were in good
shape with no rust and good smooth critical interior surfaces.

The first order of the day was to buy a new head for the ejector, which screws on
to these guns and it was missing. I located one for a few bucks and ordered it,
it fit and functioned fine.

The next item is check the timing. It would not drop the cylinder bolt into place
reliably when cocked manually at a very slow speed. A rapid single action or
double action cocking would 'sling' the cylinder far enough that the bolt would drop,
but not when done slowly. This means that the hand is not pushing the cylinder
around far enough - the hand is "too short", from wear on it and the star on the
cylinder which engages the hand. I got Jerry Kuhnhausen's book on double action
Colts, and dissasembled the little gun, my first full dissasembly for a Colt dble
action revolver. I have done or assisted in almost everything that can be done to
and for a S&W revolver, but Colts, while in the inventory, had not been cracked
open yet. Surprise - they are VERY different inside!

After 'stretching' the hand, I got the timing correct. But the gun still would bind
up in fast double action shooting with live ammo. More study showed that the
end play of the cylinder was excessive, and this lets the front face of the cylinder
drag on the back face of the barrel when the hand is pushing the cylinder around -
and simultaneously pushing the cylinder forward into the barrel. The official
Colt repair is to use a very fancy swaging tool to swage the tiny ring at the front
of the cylinder out a bit to take up the slack. Lacking one of these special tools,
and having no intention of buying one, I started studying Colt revolver on the
web. Eventually, I found an amateur gunsmith that was fixing this end shake
problem in Colt Pythons by turning off the little snout on the cylinder, then
counterboring this area for a new, longer bushing to be pressed in place. I have
the lathe that is required, but did not want to start carving on the cylinder of
a 1930s vintage Colt unless there was no other choice. I know that Ron Power
Custom makes shim washers for different locations in the S&W revolvers, but his
web site does not show any for Colt revolvers.

A feeler gage showed that the total movement of the cylinder was about .008".
I wanted to keep the cylinder off of the back of the barrel, so I decided to make
a .006" shim. A good friend is a tool and die maker, has a REALLY nice machine
shop with two NC mills and all the other tools that you need to make almost
anything. He also is a champion pistol shot and a great pistolsmith, mostly on
his own guns, with occasional assists to friends. I discussed the issue with him,
and showed him a few sketches of jigs that I had designed to make a shim. It is
not obvious that making a shim would be big deal, but the issue is that this shim
has an outside diameter of 0.400" and an inside diameter of 0.330", and needs
to be about 0.006" thick. He offered a .006" feeler gauge for material and a couple
of suggestions on how to do it better.

I used the lathe to turn down the OD of a piece of scrap stainless steel to .400,
and then drilled a 3/16" hole down the middle. I turned a .330" diameter snout
on the rod, about .100" long, then cut of this piece at about 1/2" length. I then
faced of the remaining piece and drilled it from the end with a "Q" drill, which will
drill a .332" diameter counterbore, 0.002" larger than the crane where the shim will finally
reside; about perfect. After parting the second bushing, I reamed the pair up to
a slight clearance on a 3/16" aircraft bolt. These will be the OD jig.

Now, for the jig to make the ID, I cut a small piece of 1/8" steel and a similar sized
piece of 1/4" thick aluminum. These pieces are about 3/4" by 1.5". I drilled
through the steel piece and the aluminum block and tapped the aluminum 10-32
to accept a short aircraft AN3 bolt in two places. Between these two there was
room for a 1/2" wide feeler gage. I used a piece of gifted 0.006" Starrett feeler
gauge as my shim stock.

After clamping the shim stock between the two plates, I drilled through the
aluminum, shim and steel plate with a "Q" drill, making a shim with a squared
off oversized OD, but a .332" ID hole and no damage because it was supported
fully during drilling.

Next the partially completed shim is slipped onto the snout of the OD jig and
the snout inserted into the counterbore in the opposite part of the OD jig. A
3/16" aircraft bolt runs up the middle and clamps the shim in place.

The jig supports the thin shim between two faces, and the excess material sticks
out past the jig. I roughly ground away the excess with a Dremel tool and
abrasive wheel. The final cutting off of the excess shim stock, was done with
a fine cut file until the shim was flush with the OD, which was made to 0.400"
diameter. I unbolted the two OD jig parts and had a nice, concentric shim ring
that is .006" thick and has a .400" OD and .332" ID. This is a tiny little ring and
it took a bit of time to make the fixtures and then the shim, but the shim
should last for quite a while and with the fixtures, I can make another one if I need
it.

I installed the shim between the cylinder snout and the crane and it removed
essentially all the end shake, maybe about 0.002" is left, and there is a 0.006"
cylinder gap to the barrel.

Here are some pix of the jigs and the part, and assembling it.

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In the last picture you can see the shim in place, and in the second to last the shim is
slipped onto the crane.

Double action is now smooth with no binding, and I am looking forward to shooting the
little guy.

****
This was written long ago, and I have shot it a good bit since. It can be quite accurate with
good cast loads. I got two old Ideal molds made for this cartridge, and they work well. It is
a low power cartridge, and I won't hotrod it, but it is great and with the long 5" bbl, works well.

Bill
 
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Pistolero

Well-Known Member
I can recommend Khunhausen's books.

Stretching the hand is done with a rounded, polished faced linear punch. I unsharpened a
cold chisel, put a 1/16th radius curve on the "cutting edge" and then polished it to a mirror
finish with sandpaper, like polishing a shoe.

Put the hand on a hard steel surface, and put the stretching tool on it, making sure the tool is
flat so it will stretch uniformly across the width of the hand. If it is angled, it will cause the hand to
curve, a real problem. I did one hit with a ball peen hammer, noted a visible line on the hand, and
tried it. Better but not there yet. Disassemble and another line, adjacent to the first one. This time
the hand was long enough to time properly, drop the cylinder bolt just before releasing the hammer
in very slow double action.

So, with a bit of work, a $100 non-functional gunshow junker is now a very nice little pistol, ready for
another long service run.

Bil
 
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Intheshop

Banned
Cool

I was like,all you gotta do is counterbore the......And then kept reading.

5" barrels have got to be the perfect balance of.... well,everything.
 

Pistolero

Well-Known Member
It turned out that the 0.006 shim was a bit too much. So, I used the tools again and made a shim of 0.004
feeler gauge stock. That one was perfect.

Bill
 

Pistolero

Well-Known Member
I like th 5" bbl although this is a pretty small gun, so it seems big for the small frame. It works
great, though.
 

Pistolero

Well-Known Member
And since I did that write up... this was shown to me,like four years later. he makes shims for
other revolver brands, too.

 
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462

California's Central Coast Amid The Insanity
I highly recommend Triggershims.com. Both my New Model Blackhawk and New Vaquero had hammers that were off-set to the left. The Vaquero so much so that the hammer was scuffed from hitting the frame. Ordered and installed the shims, polished the Vaquero's trigger, and both hammers are now centered in their frames.
fullsizeoutput_11f.jpeg fullsizeoutput_1d0.jpeg
 

oscarflytyer

Well-Known Member
OK! Love this! I have been picking up old Colt DAs in 32NP/S&WL, 32-20 and 38 SPC. Old Smith's too, but really like the Colts better. It is great that you rescued this one. And everything I have read/heard is that a Smith and a Colt are Apples and Oranges.
 

Pistolero

Well-Known Member
Yep, not much at all alike inside. S&Ws are easier and more durable. Colts tend to either be perfectly made, and timing
holds forever, or they are slightly off, and due to a very unforgiving design, tend to pound out of time relatively quickly.

And S&W are SUPPOSED to have a bit of rotational slop in the cylinder, it is a design feature, not a problem, take my word for it.

Bill
 

CZ93X62

Official forum enigma
That revolvers work at all is a lot like helicopters and honeybees staying airborne--no reason on earth that any of these systems ought to work worth a darn, but darned if they don't.
 
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Ian

Notorious member
I have always had thise same sentiments, Allen. As a kid it amazed me that revolvers were still being made, in theory they seem to barely be capable of functioning at all, like the "harmonica pistol" of the black powder era.
 

Rick

Moderator
Staff member
It's always amazed me that anybody ever hit anything with a revolver but a good revolver will absolutely amaze.
 

RicinYakima

High Steppes of Eastern Washington
It all depends upon where and when you were raised. Where I came from, autos were junk, as most were surplus 1911's that wouldn't hold 6 inches at 25 yards, or Spanish 32's. A Colt's Officer's Model or S&W Heavy Duty would out shoot anything around. Colt Woodsman was the most accurate 22 and only auto worth owning. FWIW
 

CZ93X62

Official forum enigma
Autopistols have come a long way since I first became interested in shooting them in nineteen-ought-sixty-eight or thereabouts. I don't have a strong preference for either system--roundgun or slider. My Gold Cup 45 and my Colt OMT run about neck-and-neck for accuracy, but that 586 x 6" might give them a run for their money.
 

Rick H

Well-Known Member
When I cut my teeth you couldn't give me a Colt revolver, even a Python. Colt just never understood how to make a double action revolver that didn't have a hitch and lurch in the action...S&W only thank you. On the other hand, you couldn't give me a S&W autoloader, John Browning understood auto's and Colt 1911's were king.

Funny what happens over the years....carry a S&W Shield every day now.
 
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RBHarter

West Central AR
With age comes enlightenment ?
I had a number of revolvers before I got to a low mileage SS Sec 6 . I thought I'd found nirvona in a double action trigger .........about 5 years later I got to shoot my grandfather's M10 , way to make that Ruger trigger feel like 5 miles of gravel pot holes ....... Mom's 1917 Colts was only a fair cover of the 47' M10 as far as the trigger goes . It was smoother than the Ruger after a very deep cleaning but not like the Smith . Then the 1917 circa mid 1918 came along ......... I can't fairly even begin to use that as any kind of a bench mark . It would just set the bar too high short of pro custom work .

I've shot a couple of 1911s , GI class , and they are nice . They do work with all manor of loads as long as the nose feeds it's a go . But to be completely honest they just felt heavy and slow in function . Maybe I was being over critical of the gun when working up a load for a guy or maybe it just didn't fit me or maybe I'm just not a 1911 guy ......the 38 Super Auto 1911 is still on the wish list but ........ I much prefer the P35/High Power it just feels better and more balanced but it would probably not be a great 5" target gun .
The latest carry gun was a Springfield Armory XD and to be frank it does everything the 1911&P35 do better ....... It may be just a perception thing and fit though . Nothing wrong with 15 rounds of 40 either .
I only shot an early S&W composite auto in 9mm and if that whippy no return to point of aim oversprung wonder is a typical example it's no wonder they overhaul the line every couple of years .
I like the G42 ......... probably because it feels and runs just like the XD but scaled down to 380 .

It's all perspective and personal feel I guess it's been nearly 20 years since I shot that Smith auto or a 1911 so maybe my tastes have changed . I know my recoil tolerances have since getting off the wrong side of a motorcycle and breaking that funny little grey area that's both and neither wrist or arm .......
 

CZ93X62

Official forum enigma
I have A LOT of 5" D/A revolvers in the safe, and REALLY miss the 5" Model 27 that had to go during my hiatus from work c. 1999. (Don't get hurt at work while working for Riverside County--it's like "Mission--Impossible"--they will disavow any knowledge of your existence. There are dozens of deputies with similar stories.)

Colt vs. S&W banter was a feature of my early work life at the Department. Ruger D/As were allowed for a time, then dropped in 1987 when we added autopistols, and re-added about 2000 when the agency finally noticed that Colt D/A revolvers kind of disappeared. That lot (Academy staff) must have a lot to think about, I guess. I like all three makers' products, though my reasons for each preference vary.

With the onset of the Copper Condor Cuddler Bullet Era in this carjacker's theme park for hunting use, I think the Rugers will be getting the bulk of the CA hunting assignments. Folks don't run steel shot through their fine S x S shotguns from 100 years ago, I am sure as h--l NOT going to run copper bullets down my pre-27 6.5" barrel, either. That's what Rugers are made for--heavy lifting and stern duty. Their warrantee coverage is first-rate, also.