1973 Model 66 Problems

[Old cop]

I'm having light strikes on random chambers in the cylinder, the cylinder sticks a bit when I try to open it & the cylinder does not spin freely when out of the frame.

I picked this gun up from the original owner who purchased it in '73, fired 5 rounds and put it back in the box until I got it last year. I lubed it, checked the strain screw (it's tight) and the ejector rod works perfectly (not bent & tight). I ran 100 rounds of factory range ammo through it today and experienced two light strikes. Both primers had a good dent and the rounds went on the second try. I plan to try some factory self defense ammo but wondered what I might be overlooking before seeking out a gunsmith. I'm a very experienced revolver shooter so this has me stumped.

 

[murphydog]

A good flushing with aerosol brake cleaner followed by a light lubrication. There may be 46 years of crud in there.

 

[UncleEd]

When you say you "lubed it" does that mean
you took the side plate off, removed the cylinder, etc.

I suspect Murphydog is correct that it is just jammed
with dry oil that the previous owner may have
too, too liberally applied.

Revolvers need very little to no oil. I recommend
Rem Oil if you open it up and clean it out and
wipe off all the main parts. A few drops on contact
points is about all that's needed.

 

[Old cop]

Thanks, I have not removed the sideplate and am a bit nervous about that (I've watched a few videos). I did clean the gun a few minutes ago and the cylinder now moves freely but the light strikes are still a concern. I doubt the previous owner over-oiled the gun since it was bone dry when I got it. Next range trip I'll shoot up a box of factory hollow points, +P & .357, to see what happens.

 

[ken158]

A "good dent" in the primer indicates ammo issues as a start. A light indent would indicate strain screw backed out as first thought and go from there.

 

[WI357SIG]

My Model 66-1 with Warm Loads

My first center-fire revolver was a Model 66-1 with six-inch barrel purchased in 1980. I shot various bullet weights including some warm .357 reloads. One day it lost the timing and I sent it back to S&W for repair. It got a new non-recessed cylinder; they said one of the chambers was swelled. Not really noticeable to the naked eye. Back in the late 80's, it cost over half the purchase price for the repair and probably reduced the current value by half as well.

I Got a 686 and considered that a more robust solution. I retired the Model 66 and haven't shot it in over 20 years.

Anyway, enjoy the Model 66, from my experience, I would avoid .357+P.

 

[Old cop]

A "good dent" in the primer indicates ammo issues as a start. A light indent would indicate strain screw backed out as first thought and go from there.

I'm not sure what a good dent vs a light dent in a primer is but the impressions from the firing pin look alike on all six casings. As to the strain screw, it's tight so if it was ever backed out I can't tell and it will not tighten down any more than it already is.

 

[Texas Star]

First, I'd give the gun a normal cleaning and light lube. I use Break-Free CLP.

Then, I'd use new commercial ammo. I think that "range ammo" is probably your problem. Never try a new gun first with questionable ammo!

 

[merl67]

One other possibility is that someone shortened the main spring strain screw trying to get a lighter trigger pull.

 

[stu1ritter]

One other possibility is that someone shortened the main spring strain screw trying to get a lighter trigger pull.

Perhaps someone "over-shortened" the strain screw as this is the correct technique (as per the S&W Armorers manual) to adjust the mainspring setting. For .357 the service weight is 56 oz. and properly polished and tweaked internals from the Performance Center were reduced as far as 42 oz. Just weight the hammer pull and adjust as required.

Stu

 

[stansdds]

I'd give the lockwork a good cleaning and proper lubrication first, the old lubricants may have turned to gum.

 

[Old cop]

Thx for the info re: shortening the strain screw, I would not have considered that. I called the original owner, a retired cop I used to work with, he said the screw was not changed. He purchased the gun, test fired 5 rounds and put it in a safe in 1973. I measured the double action pull @ 9 lbs.

 

[Iframe32s]

Experienced an issue of the cylinder not spinning freely after firing lead handloads in a new J frame. Soft lead fragments gummed it up. As alluded to by others, I'd give it a good cleaning before doing anything too invasive.

 

[UncleEd]

DA pull at 9 pounds.

Standard for Smith is around 12 pounds.

At some time someone was inside and
changed springs or something and at the
same time probably over oiled it.

 

[jimmyj]

Replace the mainspring and mainspring tension screw with new ones

 

[StrawHat]

DA pull at 9 pounds.

Standard for Smith is around 12 pounds.

At some time someone was inside and
changed springs or something and at the
same time probably over oiled it.

Maybe, the standard is not carved in metal. I also attended the armorer's school and saw trigger pulls all over the scale. It may just be one of those good pulls thatwe often hear used to be standard.

Kevin

 

[t4terrific]

A "good dent" in the primer indicates ammo issues as a start. A light indent would indicate strain screw backed out as first thought and go from there.

Good point. I'd remove the grips and make sure the mainspring tension screw is snug. If it's loose, that's probably the problem ( and a common one, since it's an easy way to lighten the DA trigger weight ).

Either way, lube and a little cleaning is needed for the moving parts on an old gummed up revolver.

 

[serger]

Go to the hardware store, buy a 1/2 gallon of mineral spirits & a
empty 1/2 gallon paint can. Pour mineral spirits in the paint can
til it's half full and after you remove the grips put the revolver in
it barrel up. The lock work on the revolver should be submerged
from the forcing cone down.

Let it sit for a few days. Remove it, shake out the excess mineral
spirits. Put the gun in the sun to dry. After it's dry, try it again.
Only thing you may need to do is hit it with a few (very few)
drops of light oil remembering that most gun oils are just glorified
mineral oil if you can read the safety data sheets required by law
to be available from the peddlers.

 

[mikerjf]

Do all rounds slide in the chambers freely?

No expert, but I can imagine cruddy chambers letting a case sit 'almost' all the way in, and then the firing pin hit pushes it the rest of the way home (and soaks up some of the firing pin energy doing that), resulting in a weak hit.

 

[Old cop]

Do all rounds slide in the chambers freely?

No expert, but I can imagine cruddy chambers letting a case sit 'almost' all the way in, and then the firing pin hit pushes it the rest of the way home (and soaks up some of the firing pin energy doing that), resulting in a weak hit.

Yes, all rounds (.38 and .357) slide into the chambers w/o sticking. Gun only had five rounds fired before I got it.