S&W crane screw mystery


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Hawk
June 30, 2008, 09:51 PM
So I notice that in the Jerry Miculek "trigger job" DVD he makes note of the spring loaded screw that holds the crane in the frame on the model 10-10 that stars in the production. It's rather like the Python cone-pin / spring / screw-cap arrangement but all one part.

But I notice that my 28-2 crane screw doesn't have any spring to it - it isn't even "cone headed"; it's rather square-ish on the end and solid as Gibraltar.

This I assume to just be life and what I get for buying used. Surely the 686-"no dash" has the right screw. Nope. Looks just like the rigid 28-2 article - no resemblance to a spring-loaded-cone headed gizmo whatsoever and looks just like the 28-2 flat-ended-rock-solid item.

At this point my option is to yank the crane screw from every S&W I own or post on good 'ole THR for an answer:

Did I hit two flukes right in a row or do some S&Ws not have a spring loaded crane screw? Or is the Jerry M. 1998 DVD and 10-10 the anamoly?

It doesn't seem likely I could get two S&Ws right in a row with the crane screw replaced by some bogus article but my luck with used revolvers has "statistical clustering" written all over it sometimes...
:eek:

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Old Fuff
June 30, 2008, 10:46 PM
Your trouble is that you don't ever buy the books I tell you to... :banghead:

The model 10-10 came out in 1988, and the engineering change involved was: New yoke retention system.

The model 28 was discontinued in 1986, the dash-2 version in 1982.

The 686 (no dash) became history in 1986, but in 1988 at 686-3 they changed the yoke retention system so it was like the 10-10.

For some reason that I don't fully understand, earlier production Smith & Wesson revolvers don't have improvements that were introduced after they were made. Somehow I must be missing something. :D

HighVelocity
June 30, 2008, 10:57 PM
I actually prefer the old style solid screw over the spring loaded one. Once at a pistol match, during a fast reload, I managed to push on the cylinder hard enough to snap off the spring loaded detent on the screw and almost sent the cylinder and crane to the ground. :eek:
This happened on a Performance Center 627.

Hawk
July 1, 2008, 07:27 AM
For some reason that I don't fully understand, earlier production Smith & Wesson revolvers don't have improvements that were introduced after they were made. Somehow I must be missing something.

What we're missing is that engineering improvements don't always have to be placed in quotes, as in: engineering "improvements".

It would appear that in 1988 S&W actually went to a more expensive part - perhaps not universally accepted as "better" but surely costing more money than a straight screw.

I was under the mistaken impression that S&W was on a steady march to production expediants and cheaper parts; hence it simply didn't occur to me that they put a speed bump in that highway by introducing a more expensive part in 1988. Now I know. I wonder if there might be other examples of "improvements" actually being improvements?
;)

ETA: BTW, there are a bunch of .002 Power shims on their way - both for the hammer and trigger. I expect the weekend of the 4th to be a voyage of discovery and possibly no small amount of cussin' at the Hawk household.

Mysteries that will likely be worked out include how the shim can go on the sideplate without binding up the hammer (it isn't as loose as I once reported - things seemed quite snug in there).

The case color on the hammer right side is scored to beat the band but in the area of the sideplate just below the where the hammer meets (or rather, shouldn't) the frame. The sideplate is rough as a cob on the inside but the bluing isn't worn. How the color case got scored rubbing against a blued part that isn't worn seems like the highest order of voodoo but we shall see.

The parts are all in a tupperware container awaiting the postperson.

Guess I'm going to have to cave on the Standard Catalog. It appears Kuhnhausen doesn't have much to offer on real recent stuff - if there's anything in there about the 1988 stuff it's well hidden.

Master Blaster
July 1, 2008, 08:07 AM
MY guess as to why Smith & Wesson went to the spring loaded screw, is that they got tired of folks sending in their revolver for repair when they got the screws mixed up and put the longer screw in the hole for the shorter crane screw, and then had problems opening and closing the cylinder.

Hawk
July 1, 2008, 08:53 AM
I'm new enough to these rotational firearms I put the screws into little pill holders in the order they came out. Not much chance I would get them crossed up although the middle one looks pretty much the same as the crane screw.

I have a personal history of getting used revolvers with the crane retainer backwards and upside down from a previous owner - specifically a Python that had the spring against the crane, followed by the plunger (backwards) held in by the screw cap (cup?).

Every time I get one of these older S&Ws or any DA Colt I view it as a mechanical diary of the previous owner's likes, dislikes and abilities as a shadetree mechanic. I suppose most of these things made it to the used market without having been molested but it'll take a couple more "unenhanced" purchases before I'm not seeing illusory gremlins everywhere.

Fortunately, Fuff generally gets me back on the straight and narrow.
:D

Old Fuff
July 1, 2008, 09:42 AM
It appears Kuhnhausen doesn't have much to offer on real recent stuff - if there's anything in there about the 1988 stuff it's well hidden.

The manual covers most Smith & Wesson revolvers made from 1946 through the 1997 -99 period when the new MIM lockwork and despised lock were introduced. So far no one has written a manual that covers these. In my opinion they don't respond to conventional tuning techniques very well.

For detailed information on hammer and trigger bushings, look in your manual on Book I, Page 53 Check Hammer Drag.

Over the years, Smith & Wesson did make some real improvements, but I'm not sure it was intentional. :neener: :D

Old Fuff
July 1, 2008, 09:50 AM
Previous work by unskilled former owners is always a threat when buying a used gun, partly because of getting rid of the evidence makes it probable they'll show up on a gunshow table or dealer's used gun case.

The first thing I do when picking up a prospective purchase is eyeball the screw heads carefully. If there is any sign of buggered or battered screw slots the gun quickly goes back to the seller - unless a serious discounting of price is part of the discussion. :scrutiny:

Master Blaster
July 1, 2008, 12:58 PM
The first thing I do when picking up a prospective purchase is eyeball the screw heads carefully. If there is any sign of buggered or battered screw slots the gun quickly goes back to the seller - unless a serious discounting of price is part of the discussion.


Me too, the next thing I do is check for hammer Push-off a clear sign that bubba did a trigger job and ruined the hammer/ sear.

Hawk
July 2, 2008, 10:58 AM
I gather "hammer push off" is when the hammer, when cocked for single action firing, can be pushed forward without pulling the trigger?

Found this:
http://smith-wessonforum.com/eve/forums/a/tpc/f/580103904/m/6171078242

Anyhow, I note that a S&W "trigger only" adaptor is available for the Power Series 1 jig I bought a long while back - presumably these "hammer push off" guys can be saved?

In other news, I note a minor amount of run-out on the extractor rod. By "minor" I mean that, with the cylinder closed, hand and stop removed, there's no bind. Safe to say "No Bind" == "Don't mess with it"?

This is fun but I do wonder about the repeated assertions that revolvers are "simpler" that I see in the "vs" threads. Even the cylinder latch does double duty as a hammer block of sorts - analogous to a "disconnector" perhaps?

Old Fuff
July 2, 2008, 11:24 AM
I gather "hammer push off" is when the hammer, when cocked for single action firing, can be pushed forward without pulling the trigger?

That would be correct.

Anyhow, I note that a S&W "trigger only" adaptor is available for the Power Series 1 jig I bought a long while back - presumably these "hammer push off" guys can be saved?

Sometimes: But only if the full-cock notch on the hammer hasn’t been messed with. If the situation can be saved the work must be done on the trigger. Again, details are explained in your Shop Manual.

In other news, I note a minor amount of run-out on the extractor rod. By "minor" I mean that, with the cylinder closed, hand and stop removed, there's no bind. Safe to say "No Bind" == "Don't mess with it"?

Probably. Unless you have a special fixture trying to detect and fix such run-out is difficult. Also, binding may be caused by a bent yoke barrel, and this possibility should be looked into first.

This is fun but I do wonder about the repeated assertions that revolvers are "simpler" that I see in the "vs" threads. Even the cylinder latch does double duty as a hammer block of sorts - analogous to a "disconnector" perhaps?

There are two contexts here. First, simpler to use, and second, simpler to tune or repair. I find the lockwork in double-action revolvers to be simpler the that in some single-action/double-action pistols. However in working with or on revolvers there are issues that go beyond the lockwork – something that many tinkers don’t realize. But you are learning…

Hawk
July 2, 2008, 12:22 PM
You are correct - I hadn't considered DA/SA semis. I got reasonably comfy with 1911s, most particularly the mutant variations thereof, and find them pretty simple and straightforward compared to the round guys. Possibly just a familiarity thing.

Yoke barrel looks good - at least I'm not finding any binding anywhere - I checked the cylinder for bind only because of visible runout but there's nothing there. The pull seemed heavy but not bound - almost like an "extra power" spring found its way in there. It may well be just my perception due to the sharp edges on the trigger wearing a hole in my finger. I need to get a trigger gauge that reads past 6 pounds - it was plenty good enough for the 1911s but doesn't tell me much in the current context.

Why do I always think of these things after the Brownell's order is packed and shipped?

Old Fuff
July 2, 2008, 01:46 PM
Old Fuff always say.... Use brain before pocketbook. :scrutiny:

I need to get a trigger gauge that reads past 6 pounds

1. Take cut-off 1/2 Gal. milk container (or anything similar), make two small holes at top, and tie string from one side to the other to make handle.

2. Use old wire hanger to make hook that will go from face of trigger to handle on container.

3. Hold revolver muzzle-up, place hook across trigger face, attach other end of hook to string/handle on container and lift container off of ground.

4. Have someone pour lead shot, bullets, sand (whatever) into container until the trigger is pulled through full cycle.

5. Weigh filled container to determine approximate trigger pull.

You may have to remove the stocks to keep the hook from being too-far outboard.

6. On those revolvers likely to be used much in double-action, the Old Fuff usually removes serrations or uses trigger that doesn't have any. Or you can use small piece of emery cloth to dull the sharp edges of serrations to make finger feel all-better.

Oh, and Model 28 Highway Patrolman intended to be police gun. The springs were designed to insure absolute reliability.

Hawk
July 2, 2008, 02:34 PM
As one who derives income from custom architectural elements I should have recognized that apparatus as a rustic "door closer". Bucket full of rocks, rope, pulley, adjust closing speed by adding / removing rocks.

I would never have guessed I'd own something where I'd need a bucket to measure trigger pull - never say "never" I guess. Kinda makes my whining that Dawson wouldn't drop the pull on my last STI below 4 pounds seem rather silly in contrast.

You must be that bad influence my mother used to warn me about - I just noticed the other day that, with the addition of the 28-2, my meager accumulation of revolvers just overtook everything else as my most common firearm type. Rather of a surprise given the short time I've been looking at the things.

But then, it doesn't take much if I only owned two semis, 1 rifle and a half a shotgun. If my wife should read this, that's my story and I'm stickin' to it.

;)

Old Fuff
July 2, 2008, 05:37 PM
If you send me the Model 28 I won't tell your wife.... :eek: :evil: :neener: :D

One time I had to write a report on a European copy of the Browning Hi-Power. I found the trigger pull to be well beyond any gauge I had so I got out the ol' bucket...

Turned out to be 27 pounds...

The mainspring could have been used in a pick-up truck suspension.

Hawk
July 5, 2008, 04:43 PM
So, I chickened out.

Got to stoning the trigger and rebound slide per the Jerry Miculek DVD, got all twitchy thinking about the "push off" thing, left the hammer and cylinder stop alone, reassembled with a Brownell's "reduced power" main spring and "middle" rebound spring.

It seems some improved but nothing to write home to mom about. It did however work real well at the range today although the S&B cases seem to stick. Guess I'll try getting agressive with a brush.

In fact, it worked better than my "686 of best trigger ever" which has a noticibly lighter main spring installed by who-knows-who which left 4 out of 50 S&Bs unlit in double action. I'm considering leaving it that way and just using other ammo (Cunningham has a note about S&B and Fiocchi being "harder"). I did, however, get several of Brownell's "reduced" springs and one "standard". Their "reduced" is noticibly "heavier" than whatever is in the 686. Choices... I'm so confused. Maybe a Brownell's "reduced" and trade my least-suckage DA trigger for 100% reliabiltiy...

I guess a certain amount of DA suckage is needed if one is to use hard-as-a-rock primers.

http://www.grantcunningham.com/blog_files/5664e330f77e0d21fdac0f877139ab5c-323.html

Too bad I can't delegate the decision. I'm going to miss that trigger if I replace the "spring of extreme wimpiness".

Jerry Keefer
July 9, 2008, 08:37 AM
Hammer push off may not be a product of amateur smithing. Often times, it is the hammer hook as it comes from the factory. As tooling wears, the inside corner is often not as sharp and square as it should be. The hook itself is very short;. . It doesn't take much of a radius in the corner to effect the trigger engagement. Hammers should be inspected under a tool makers micro scope or high magnification optical comparator to determine the accuracy of the cut. I think you'll be surprised. Mass/assembly line production has its faults.
The old wives' tale (myth) that the hammer is ruined and can not be touched is not true. The hook can be squared and trued with the proper tools and fixtures...
Once the hammer is prepped, the trigger engagement angle must be adjusted to be compatable with the hammer when in the single action position.(cocked)
Again, a job for the micro scope and appropriate fixture. Not to be condescending, but stoning the trigger as the link depicts, is truly
a shot in the dark.
Take care
Jerry

Hawk
July 9, 2008, 09:17 AM
The link appeared to be a "shot in the dark" to be employed only if "push off" was already an issue. I had posted it only in an effort to ascertain if I had the term "push off" correctly understood.

The Miculek DVD has one staying clear of the single action portion of the trigger. I was only getting twitchy because the DA and SA surfaces are a little too close for my personal comfort level and I couldn't be certain what had gone on before.

What fixture are you referring to? I have a Power series I jig and S&W adaptor ordered but, for now, it's strictly insurance.

Jerry Keefer
July 9, 2008, 10:07 AM
Hawk;

There are none available commercially that I know of.
Those of us that specialize in that work make our own...
When stoning the trigger engagement area, we need to know the existing angular relationship. That relationship may need to be increased/decreased or remain as is and only dressed.
There is no way that can be determined with the naked eye..

Good luck

Jerry

Hawk
July 9, 2008, 11:09 AM
Thanks. The Power jig has provided yeoman service on several 1911 derivitives but I'd rather leave these revolvers the way they came. The 28-2 is a good one to "go to school on" as it was near unusable as received. Still, I don't intend to push my luck.

The 28-2 is "in time" but the observation that one chamber is barely so while others are "comfortably" so leaves me perplexed. Not only does one model of older revolver differ dramatically from another of the same model and roughly same manufacture date but none of the six chambers seem to time precisely like their neighbors.

With ocassional exceptions I manage to refrain from snarky comments when "simplicity" is noted as an attribute of revolvers - but it tries me sorely. Clearly, those folks have never compared a 1977 28-2 to a 1911 derivitive. You may be assured I poke at the innards as little as possible. They all remind me of RCModel's comment on 19th century Colt DAs: working on them is "Like trying to stack greased BBs".

:D

Jerry Keefer
July 9, 2008, 12:12 PM
Hawk;

An observation over the years has been that the chamber circle (layout) is normally held to extremely close tolerances by S&W. The C/C distance rarely varies more than .001 which is quite good, so their quality control on the cylinders must be a priority. The alignment variations usually are a result of tolerance stack and other factors, such as the C/L of the barrel tenon thread root line; yoke alignment; cylinder /yoke tolerance..etc. & factory gas rings are notorious for poor fit...
It has been said that, "if the quest is accuracy, the frame revolves around the cylinder..."

Old Fuff
July 9, 2008, 03:38 PM
Smith & Wesson STRONGLY RECOMMENDS that hammer notches not be stoned or altered. Jerry Kuhnhausen, in his S&W Shop Manual remarks;

If the notch shows any evidence of filing, stone work, low spots left by corrosion, is chipped or has a corner missing - replace the hammer body.

I fully agree. I have seen far more hammers ruined by stoning with no apparent improvement (or maybe too much improvement) to the trigger pull. While all hammers are not perfect, it is unlikely that any gun owner, and most gunsmiths, have the equipment or knowledge to know what the correct angle(s) are, and using too soft a stone with a rounded edge will get you into trouble fast. The notch in a S&W revolver hammer bares no relationship to a 1911 pistol equivalent, and I have seen plenty of them ruined too.

Smith & Wesson single-action trigger pulls seldom need much improvement so far as the hammer’s notch is concerned, and any issues can usually be best addressed by working on the trigger. That said, often any problems are not caused by the notch/trigger relationship in the first place. On many occasions I have seen substantial improvement with the whole action after doing nothing more then through cleaning and fresh lubrication.

Hawk
July 9, 2008, 04:43 PM
As you note, the single action was just fine - haven't found a S&W yet where the SA wasn't good.

The Miculek DVD, if I remember correctly, had us hitting the bottom of DA pinned sear just to square the thing if needed. The hammer body proper wasn't to be touched. My memory may be fogged - I'll watch it again but that sounds right.

Miculek seemed to go to some lengths to warn amateurs away from the parts that could ruin the gun if done incorrectly. The rebound slide seemed the only place where one could exhale with impunity.

Jerry Keefer
July 10, 2008, 07:54 AM
Fuff;

What's not similar about a 90 degree notch?? The same mechanical function takes place whether it is a 1911 or S&W. The notch on the S&W may be much shorter, but it is 90 degree, and the same..
S&W and Kuhnhausen recommend against stoning because it is impossible to accurately stone the delicate notch by hand. It is very simple to do with the proper precision machinery. High RPM carbide cutters flooded with coolant produce a perfectly squared, mirror finish. In fact, the S&W mass produced hammers are crude by even the most basic micro finish standards. I am not attacking your Guru status;
I merely mentioned to Hawk that some things can and are done routinely by some advanced smiths...

Take care
Jerry

Old Fuff
July 10, 2008, 09:51 AM
What's not similar about a 90 degree notch?? The same mechanical function takes place whether it is a 1911 or S&W. The notch on the S&W may be much shorter, but it is 90 degree, and the same..

The Smith & Wesson notch may be similar, but it’s a lot more shallow (.006” - .007”) and harder. As I pointed out a lot of easier-to-do 1911 pistol hammers have been messed up with a stone too. And unlike the 1911, I am unaware of any commercial fixtures for working on S&W hammers, and the hardness of the stone (if a stone was used) and its shape would be critical.

S&W and Kuhnhausen recommend against stoning because it is impossible to accurately stone the delicate notch by hand. It is very simple to do with the proper precision machinery. High RPM carbide cutters flooded with coolant produce a perfectly squared, mirror finish. In fact, the S&W mass produced hammers are crude by even the most basic micro finish standards.

And of course a revolver owner is likely to find that his local ‘smith is set up with such machinery and the experience to use it. Lacking the access to someone that does have the necessary stuff what is a gun owner or local gunsmith likely too do? Finely, a micro finish on the notch is not necessary to obtain a acceptable trigger pull that is within factory standards for weight-of-pull.


I am not attacking your Guru status; I merely mentioned to Hawk that some things can and are done routinely by some advanced smiths...

And I’m not attacking your supposed status as an “advanced smith,” Just pointing out some real-world realities. Guru status is debatable so far as the Old Fuff is concerned, but to the degree that it exists it is base on this forum’s long experience with what he posts.

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