Hi folks,
I bought a new model 66-8 about a year ago. For the most part I really like it. My problem is that it suffers powder fouling on the yoke and causes the cylinder to bind up. Happens after 70 - 90 rounds with Titgroup powder, maybe 40 - 50 rounds using Unique and two boxes of Remington factory ammo. These were all 38+P level rounds so low pressure compared to 357.
This isn't fouling on / under the star and the ejector rod isn't getting loose. Nor is the hand binding. After I take the cylinder off the yoke and clean the yoke I'm good for another session.
Never had a similar problem with either an older M15 or 686.
I think this issue might be limited to the new model 66 only.

I wanted to use this pistol to get back into PPC matches so it
needs to be able to go ~150 rounds without cleaning.
So, has anybody else had similar problems? If so what did you do to fix it? Anybody have any suggestions?
Thanks in advance.
Ira

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Your model 66 has a Lifetime Warranty and I would suggest that you use it. Because the ONLY things I can think of to explain this are a missing or improperly installed Gas Ring or a Barrel/Cylinder gap that is well out of tolerance. Since these aren't something I would attempt to fix on a Kitchen Table I think that you should have the factory correct the problem. I would also suggest that when you send your revolver back to the factory you leave it in the As Fouled condition that is causing problems. Because the Warranty Repair section has a bit of a reputation of firing a few test rounds and shipping it back if it seems OK. To insure they are well acquainted with your dilemma let them see it first hand.

This will not be news to the repair department. The flat filed underneath older K frame forcing cones was a stress inducer that caused a significant number of them to crack. In the 66-8 the top of the yoke was lowered so that flat would not have to be cut. That did not leave space for a gas ring. It was a trade off for the engineers. To maintain a good double action pull the cylinder must be removed and the yoke cleaned frequently in exchange for longer barrel life with .357s.

As a cost saving change about a year and a half of K frame production ending during 1977 were also made without a gas ring. Those revolvers are said to have a "gas ring on the yoke," but in reality, like 66-8s and 69s they had no gas ring at all. Like your 66-8 they infamously fouled during PPC matches. Handejector has written that he was so frustrated with his PPC revolver that he will never own another K frame without a gas ring. In 1977 S&W was forced to admit the "gas ring on the yoke" was a failure and went back to installing gas rings in all their cylinders.

Since PPC is ordinarily shot with low power full wadcutters I would not choose a 66-8 for the sport. Its stronger forcing cone is no benifit but its lack of a gas ring is a serious detriment.

I had a model 66 when they first came out, and I have acquired another M66 no -. I believe the problem is the M66 is a clone of the M19. And built to the same specks as as the M19. The problem is they are made of two different metals one of steel one of stainless steel. As I found out with heat they expand at a different rate. Try this shoot the M66 till it starts to bind. Let it cool for 20 min with out cleaning it. Try it again and see what happens. Also you might try different powders that don't have as much residue/fowling.

I had same problem the first time I shot some light 357 mag Titegroup and Bullseye loads. Was bound up after 30-40 shots . I have switched powders and started to use a little Remington dry lube after cleaning cylinder area . I now use AA #5, 2400,and Trail Boss ,all loaded with 158gr lead SWC . I have shot as many as 200 rounds at one time without any binding at all. I have gone over 500 rounds without cleaning cylinder and haven't had any issues with binding.I've also have shot jacketed 158 gr bullets behind Win 296 with no problems. When I first had problems at range I was able to free up cylinder with some Remoil that I had in my range bag. When I cleaned pistol at home after binding there was a lot of carbon on the cylinder shaft,I don't know if carbon - powder residue was the total cause or that combined with heat was problem.

Howdy- the 1st Gen m-66 did not have a gas ring, and, yes, fouled quite quickly when ammo featuring cast lead bullets was fired in them. At the first engineering change, this was remedied. IF you can find a 'smith who went through S&W's armory training back in the day, one of the things that was developed was to install a gas ring and modify the crane for the needed clearance ( the later cranes were different, to accommodate the gas ring ). I own a 66 no dash on which this was done. Great shooter, but no "collector value".

Guys, thanks very much for the info. Not having a gas ring on this model really explains the problem. I'll load up a couple of batches of ammo with 2400 and 296 to see if that helps. If that doesn't do it I'll call factory service and find out what they have to say.
By the way, the barrel - cylinder gap on this particular pistol is 5 mils
Ira

Let us know if different loads help,it worked in my case but every pistol is different. I would like to know if a gas ring was installed by a gunsmith would Smith Wesson still honor their warranty?

Unique powder is just about the dirtiest powder I've tried. The high nitro content of Titegroup makes it burn hot and vaporize more lead from the bullet. Switching to a different powder might make a substantial difference. Or upping the charge to increase the pressure for a more complete burn might help too.

I would try lubricating the area with a CLP type product that will dissolve carbon that makes it there. Or you could also try plated/jacketed/coated bullets for a cleaner launch.

Hi Guys,
A quick update:
I put together 50 rounds of 357 using H110 (16.5 Gr) under 158 Gr XTP
bullets. Those left powder residue on the yoke but not enough to bind up the cylinder. So that was a step in the right direction.
I did call S&W factory service and described the problem. The fellow there said to return the revolver and sent me a FedEx shipping label. So
The pistol is now on vacation in Springfield MA. I'll let you know what happens when it gets back
Thanks again for your time, help and comments
Ira

Thanks for update hope all goes well. Will you go back to the Titegroup loads that caused the binding problem ?

When the pistol comes back I'll try the Titegroup and Unique loads to see
if the problem got fixed or at least improved. After that, I'm not sure. I
have some HS6 and BlueDot that I could try, at least for full house loads.
Around here, pistol powders availability is still pretty iffy.
By the way, does anybody have any recent experience with S&W factory service turn-around times?
Thanks
Ira

About 6 months ago I sent in a 380 Bodyguard. It was back in 9 days, but still had the same problem in was sent back for. It is now long gone.
Hope you have better luck.
I do own a 66-7 that will bind up rather quickly. I do not shoot competition with it, so it is not a big deal for me.

Just a question... are you able to put a drop of oil on the piece that binds during the competition? I'm a bit fan of CLP for stuff like you're describing. I'm at about 54-60 rounds of Winchester/Remington factory loads on my new 66-8 and I'm not seeing any binding as of yet. However, I will be watching this thread with a keen eye. I'm curious where this goes.

I know that this is not the correct forum for my question, but getting a group of Model 66-8 shooter together is not that easy. I love my gun, but have been unable to find a quality, leather holster for it. Even Galco which I believe makes S&W holsters does not make a holster for the newer Model 66s (66-8). The problem apparently is that the barrel is 4.25" in length. There may be other dimensional problems, such as barrel lug size, etc. but I do not know. It seems that a mold for this gun has not yet been made. There are some companies that I have not yet tried, e.g. Milt Sparks. Does anyone have any suggestions?

I've got over 200 rounds of factory ammo through mine. All FMJ or SJHP Remington, WWB, Speer and Federal. No binding whatsoever. Cylinder always spins freely. I clean and brush out residue in the area where the gas ring would be with with Hoppe's #9 and finish with a drop or two of Weapon Shield. So far so good, but I will be keeping an eye on it.

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M60 442 642 637 686 686+ 629

I'm saving up to order this Glaco. All reviews and write ups indicate it fits the 66-8 perfectly.

https://www.copsplus.com/prodnum1779.php

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M60 442 642 637 686 686+ 629

I use the same holster that I bought for my 4" 617 , it's an El Paso Strong side select. It's fits great and the holster is very well made.

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After removing the cylinder and the yolk and ejector for a major cleaning in all the nocks and cranny's with Q-tips etc. and everything is clean and the carbon knocked off...........

Wipe dry and add some Kroil to the cylinder system and spin it on the shaft a few times. Wipe off any grime and re-oil with the Kroil until it spins like a top. A little goes a long way.

I used Hoppes and other cleaners but this is what I now use to keep my revolvers working.

Look for the Galco Silhouette for the K/L frame, it's a very good OWB holster with a thumb snap. Can't remember the exact model number off the top of my head but they only offer this model in the K/L frame and N frame sizes. The K/L frame version will work perfectly with my model 620 (semi lugged L frame 357), a 686, or a model 67. Also because it's an open bottomed holster you can use any barrel length you wish with it.

BTW, to make snaps work much much easier use an old Mariners trick and apply a bit of bees wax to the snap. Just a dab will do you and it will act as a lubricant and corrosion inhibitor for at least a year or a bit more. I can also tell you that a product called Atlas Door Ease found in many auto parts stores and used to lubricate car door hinges and hold open detents is basically pure bees wax.

Do you have to take the ejector off to get the yoke off on the 66? Cylinder removal videos don't seem to match up with this model. Thanks.

Just remove the front sideplate screw & slide the cylinder/yoke assembly off the frame. The ejector will stay with the cylinder, just like in the OPs picture. Then you can clean the yoke's barrel.

.

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Waiting for the break of day

Did your revolver come back from Smith yet? If so how about an update on what if anything was done and if problem still exists? Thanks

The yoke will not slide over the top of the ejector rod.

The yoke and the cylinder are together and wont come apart, right?

Exactly! And I don't want to break anything...

Dont. Mine doesn't come off either. And ive never had to clean the part the OP described and his cylinder is removable from the yoke/crane. OURS are apparently NOT. My 686 has the removable cylinder like the one pictured.

I subscribed to this post and was lurking in it to try and figure out what people were taking about. Ive shot thousands of rounds through mine and have never needed to clean the yoke for binding. The last 5 times i cleaned the gun, i didn't even tear it down (as much as i could) because i KNEW the cylinder couldn't be removed from the yoke. Its a sealed unit? On mine.

So now im wondering. .....

I have a 66-8. Going to tear it down after i get home and take pictures for this thread. Im curious now if maybe we have a hidden revision? (Revised ) only pics i have now. Gotta crack open the safe and dig her out to see whats going on here......

Seems sealed yes. Even in the OP pic it seems like it has that pin on the side of the yoke as well. But, like you said, I haven't had to clean it that deep yet bc it's a new revolver but I'd like to know if I could

Ok. Learned a few things. Found the yoke part but it doesn't come off from the cylinder completely. It was dreanched in oil- because when i clean my guns, i blast em with clp. And i wiped the yoke which had some carbon? Dunno
It can be cleaned. But i haven't. And haven't had the cylinder bind- shooting 150-200 rounds at a time.
I use bullseye. Power Pistol. H110. And 2400.
My yoke hadn't been cleaned in well over 1k rounds and for some odd reason never binded.
I gun dip too. Clp. Rem oil. Hoppes.

Thanks Lou. Yep looks identical to mine. Glad to know I'm not imagining things. I know I have a lot of cleaner in the middle of the cylinder too that's why it annoys me. It does seem like the yoke would slide off if the ejector were to be removed no?

Hi guys, I recently traded into a 66-8, and as best I can tell, it's fine (I fired a half dozen test cylinders, of both 38 and 357 right after i got it, but that's it.)
Just in case though, can someone elaborate on this cylinder removal process for me, in the simplest, most idiot-proof terms possible ?
Thanks......

Remove this screw. Use a good screwdriver. then open cylinder latch as you normally would to load rounds. Pull cylinder and yoke towards the buisness end (barrel)
Thats all

I think the yoke screw would need to be removed so that the whole assembly can be removed like a 686. I wouldn't get in the habbit of removing the yoke screw just to clean a gun. You may mar the end and it wont look pretty.

Oops! Sorry I told you wrong. I didn't think hard enough on the model number in question.

That style is like on my X-frames. The knurled ejector rod knob unscrews (reverse threads, just like on regular ejector rods) first to remove the yoke.

.

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Waiting for the break of day

Interesting revision. I've seen cylinders go flying during speed reloads on well worn Guns but never asked if the yoke went with it. I wonder if this would stop that from happening. I'd like to see what the ejector rod looks like and how it retains the cylinder to the yoke.

Sparks will definitely make you one, but be prepared to die of old age before you get it. I love their stuff, however, I ordered a holster for a 5" N frame prior to shot show and still didn't have it in May. When I called, they couldn't even tell me when to expect it. I got a little ticked and cancelled the order. Now I'm waiting on someone else.

M.Hall

Thanks Taj,
Understand the old age issue very well. Need another holster; might let Sparks do both. Will just put both guns and holsters in my will in case I do not make delivery!

I would suggest that before you shoot for the day, you go over everything but the grips with CLP on a patch. The bore, chambers, inside the yoke, etc. Then wipe with a dry patch so only a film remains. Your fouling will be on top of the CLP & much easier to clean. I read it in a gun mag years ago... did it myself... and when the Dept Armorer saw how well it worked, he bought it in gallons & a couple of pump sprayers.

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Reserve Officer 9yrs

Last yr I had a S&W 29-10 that misfired a lot , I mean 4 times out of a cylinder of 6 . Sometimes it sounded like you were thumping a rotten pumpkin dry firing it .
I sent it in to the factory with a note explaining the problem . About 6 wks later it came back and was no better , so i called . I was asked if I shot reloads , I said yes , mine . I was told to stop w/the reloads and only shoot factory ammo . I knew that was crazy .
I decided the problem had to be in the frame mounted firing pin . After watching a video on youtube I fixed it myself . Removing the firing pin and cleaning thoroughly the pin and recess it sits in solved the problem . It's was a very easy fix .
This was the 2nd time in the past 12 monthsI have not had great luck with the factory . In yrs past , I had great results .
The same day my 29 was shipped in , my ffl also sent in a 28 , it had to be sent back a 2nd time . It just all depends on who , at the factory works on your gun as to how good the work will be . They must of hired several " newbies " just out of armorers school that lack experience .

As a rookie cop in 1979, we spent quite a lot of time on the range in training and fired several hundreds of rounds. Of course everyone used revolvers then. My model 66 had not yet arrived, so I fired my blued model 15 .38 Special. I remember almost everyone who fired model 66's or other stainless S&W revolvers having this problem. I never knew why I never had that problem with mine after receiving it... Now I know, the addition of the gas ring. My 66 went back to the factory 2 times, once because the cylinder was striking the top frame when closing it, and a second time because the barrel rifling just stopped, and then started again, as if they had quit for lunch. Couldn't hit the broad side of a barn with it until they replaced the barrel. From then on it was dead-on accurate! I guess those were some tough times for S&W.

The only ones that I have seen come apart like that are the models that have the the spring detent on the front sideplate screw, the spring and the screw point make a grove in the partial retaining groove in the yoke and slamming in a reload on the clock with speed loaders, like the Jet ones and Safariland2s and 3s. The yoke will separate from the cylinder on the 686's that I have seen do this.

Same. But I wonder if keeping the yoke and cylinder together would stop that type of failure.

Also, my regularly used revolvers all have varying degrees of wear sad you describe, but I don't use speed loaders - moon clips only, and I'm usually dropping / throwing them in, not forcing them...

Bill McClennon makes great stuff. He did one for my 66-8 and it fits perfect Bill McClennon Custom Gunleather

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I've also have shot jacketed 158 gr bullets behind Win 296 with no problems.

Sorry, could not resist. We all know what you mean, I just got a chuckle out of this. Kind of a "dyslexic reloading" situation. Have agreat 4th of July weekend everyone.

Anyone know the OP (original poster) and maybe know if there's an update to this? Did he ever get it back (sure he did but with no update who knows, lol)? Be nice to know what, if anything S&W did.

Only asking because this thread was linked in a forum email and after reading the thread, well, curious minds want to know.

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My GP100 did the same thing. I finally figured out the problem was me the shooter. I wasn't turning the gun completely upside down while ejecting the empties and powder particles were getting under the extractor star keeping it from seating back in the recess in the cylinder that last .001" and binding the cylinder. Make sure the underside of your extractor is spotless. Anything keeping it from fully seating will bind a cylinder.

Hmmm. The model 19-4 (1977) had the gas ring moved to the cylinder according to Wikipedia. k22fan, how can I tell if mine even has a gas ring on the cylinder? I don't know what to look for.
I don't plan on shooting it much, its more of an investment, but I would like to know as much as possible about the gun.