S&W Hammer spring adj ?

[Leadlum]

I went to the range today, and had three misfires. I did not know what was going on? I did see light dimplemark on the primer. They went off after a second try on all three. But I came home and checked out the pistol real good. When I took the grips off to check the main spring screw; it was not tight. so I Loc-tighted it with blue loc-tite and screwed it in till it bottomed out. I hope that is the correct ajd for it? IS IT ??....

[XBT]

Yup, that’s the correct adjustment. If it’s still too weak you can shim it by removing the anvil from a fired primer and placing the primer cup over the end of the adjusting screw. Test it in double action mode; it will fail there first because it has a slightly shorter hammer fall than in single action.

Although most people don’t recommend it, I will sometimes loosen the adjusting screw on a really stiff one. I’ve never had any trouble doing so.

[StarMetal]

That screw is merely to hold the spring and it should be tight all the time. A good gunsmith works on the action to make a lighter pull, not by taking tension off the mainspring.

Joe

[XBT]

Joe,
I ain’t a good gunsmith, I’m just a tinkerer who has been doing it this way for forty-five years and have no plans to change.

[StarMetal]

XBT,

I'm not trying to change you. Just telling folks what the strain screw is for. Depends on the revolver...some you can get away with doing that, but if my life depended on that firearms firing in double action mode you better believe I wouldn't mess with it. Some police departments that used revolvers frowned on it too.

Joe

[KCSO]

Before you could buy Wolf spring kits we lightened the main spring by draw filing and polishing. This was done slowly and I always checked by firing loads with the hardest magnum primer available. You develop a feel for the job, and you can lighten up a ppc gun quite a bit. I would never lighten a duty gun spring as you need that gun to go off in all kinds of weather and even if the gun is dirty. Any of the troops who got caught with the stran screw turned back were gigged by the R/O.

[carpetman]

KCSO---If that wolf spring was too stout could you maybe use a coyote spring?

[9.3X62AL]

Strain screw back-outs or grind-offs were the most common shade-tree gunsmithing found on duty revolvers back when they dominated cop service sidearm selections, and still crop up on the Chief Specials carried as back-up guns. Another not-so-brilliant monkey-wrench technique was/is to clip off a coil or two from the rebound slide spring. The universal response to all such modifications--and to the Wolff re-fits--was to remove the sidearm from service--requiring gunsmith re-certification before the revolver could be qualified with or carried. I was kind of a hard-ass about this sort of thing as bureau rangemaster, and put out a memo a month before every quals period warning the troops of this character flaw of mine.

Save the light trigger strokes for the fun/recreational guns--the weapons carried in harm's way need to be pretty much box-stock in terms of spring rates. Polished mating surfaces, or just a little Gunslick on those surfaces will do wonders for smoothing up an action.

[omgb]

I replaced the retun spring on mine and I added a lightened main spring and backed offf the screw. I got a really light DA BUT, I would NEVER have counted on this gun for defense. It was for PPC shooting only. Every so often I would get a light hit that resulted in a failure to fire. In the factory rebuild last year, I had all of that taken out and stock springs put back in. The difference in DA mode is noticable BUT, now it goes "POP" on every and any cartridge I feed it.

[Dale53]

I have "tinkered" with S&W revolvers for many years. I also shot a good bit of PPC. After many different combinations, I have come to some conclusions:

If you are going to use the gun for "business", best leave the Hammer spring at factory specs - that includes the strain screw. If you shoot a lot, which I certainly recommend, the very act of shooting lots of double action will "tune" your body. That may be all of the "tuning" that you need. Maybe a radical idea, but my primers go bang every time I pull the trigger. It is amazing how much your hand will strengthen from doing lots of double action work. What is NOT amazing, but rather a "given" is how much fun it can be. Just use those multible cavity moulds and cast bullets like "shelling corn":mrgreen: .

YMMV

Dale53

[44man]

Joe and a lot of you are correct. The most obvious result of a weaker mainspring, if it still fires, is a loss af accuracy. Triggers can and should be lightened without weakening the mainspring. The strain screw should always be tight on a S&W. Working down a stock spring is not a good idea either. Replacement springs are faster and the hammer still hits with about the same force. Wolff went to a lot of work to ensure this.
Anyone messing with the mainspring on a gun you have to depend on is taking his life in his hands. Leave it alone!
For target only it doesn't matter too much if you are willing to accept a loss of accuracy. Not me, I replace my springs as soon as a gun shows a loss.
A lot of you that can't get tight groups blame the barrel, the boolit, the cylinder and so on when it might be a weak mainspring.

[StarMetal]

I have a pinned barrel Model 19 Smith that I tuned the action up on. By that I mean I polished EVERYTHING inside that action. No rebound coil sping clipping, no grinding down the mainspring or backing off the strain screw. Double action felt like the trigger was broke and single action was....well kinda dangerous. In fact too a friend shooting with me when I lived in Tulsa and told him "Larry....now don't even place your finger in the trigger guard until you're on target and ready to shoot".....yeah....y'all know what happen huh? First shot went off straight up in the air, as he put his finger in the trigger guard and was going to come down on the target. His eyes looked like golfballs with the shock in them. I told him I told you so. Oh don't worry fellows....I done wore wore out some internal parts shooting that revolver so much and replaced them with all new and retuned it again, but with not such a light single action trigger. By the way, on the first action job, that light trigger was safe. Way to tell on a Smith is to take a empty revolver, cock the hammer back for single action, and gently push forward on the hammer with your thumb. If it goes off, your action job is unsafe.

Joe

[44man]

Joe just proved that the springs do not have to be messed with to get a good trigger pull. Well, maybe more then good!

[Leadlum]

That was the problem!. I hit the range this morning, and my groups were back to normal, and no mis-fires.
44 Man; you are right; that was the first thing I noticed was my groups were larger than normal. [To slow of lock time?]
But, I hope the blue Loc-tite fixed the problem. I don`t know how it backed out. I did not mess with it.
I shot some 250 swc-k today with unique in mag brass with std primers.
1.] 7.0grs=789low-845high
2.] 8.0grs=900low-950high
The 8gr load seemed to shoot a little better, might have just been me though. I only had 20 cartridges left of the 7.ogr load from yesterday; and it takes me a little bit to settle down, and start shooting good. By then I was shooting the 8.0gr loads; by then I shot 15 rds into 3" @ 25yds. Not great, just ok. But I havn`t shot in a few months.
Gun cleaned right up thanks to Felix, and his felix lube, and Ed`s Red solvent I made up. Great stuff. Thanks guys for all the help. I love this site. Keep it safe.

[StarMetal]

Well I figure I'll polish all friction and pivot points first. That doesn't require replacement and it's a good idea anyways. Don't know how savy everyone is about revolvers, but the smiths have even gone as far as putting miniature roller bearing in the hammer to ride on the pivot pin. Even polishing a coil spring improves it's function if it rides inside a hole...polish the inside of the hole too.

I met one of my best friends one day at the Tulsa indoor shooting range. I had the same Model 19 I spoke of in the other post. This fellow was a real gunsmith...he started building match 1000 yard competition rifles and then moved on to custom 1911's...and some other stuff. He saw my targets as I placed them on the counter and started to BS with him. He said may I please see your revolver. He gave it a good going over and big smile come over his face. He aske who had done the action job. I said that I did it. He asked if I was a gunsmith. I said no...I was just an amateur one. He said it was damn good. I thanked him. He gave me one tip and later did it at his shop and that was he replaced the rear sight forward screw with a better bigger screw with an allen socket screw. He asked had I noticed how they come loose all the time even if you loctite them. I said yeah, I did. Well that cured that and all my Smiths have that fix now. We became really good friends. One other thing he mentioned was how well polished my Model 19 was from the factory. He said I was on the tail end of when they stopped that to go to a less polished finish.

Joe