Lowest mainspring weight

[JFrames4ever]

In practice not theory, which kind of S & W action can use the lowest mainspring weight. I.E firing pin on hammer nose, or firing pin in frame. That is within frame size.

 

[Roller Delayed]

I'll bet this is pertinent:
CYLINDER & SLIDE S&W REVOLVER EXTRA LENGTH FIRING PIN | Brownells

So I'd assume the fixed firing pin. But the extended frame pin might make up the difference entirely.

 

[JFrames4ever]

Makes sense

 

[Protocall_Design]

They can both be equal. If you want an extended hammer mounted firing pin, you can dismount it, grind .005 to .010 off the face of the hammer on a disk sander (keeping the original angle), and remount the firing pin. Then it will go further in by the amount ground off the hammer. If you do this, check to make sure the hammer nose (firing pin) is not hitting the hammer nose bushing. See if it can wiggle a bit with the hammer all the way down. Sometimes the hammer nose needs a bit filed off in the curvy areas.

For the lightest reliable spring tension, use firmly seated Federal primers. Standard or Magnum both work fine.

 

[stu1ritter]

The factory spelled out the hammer lift weights in the S&W Armorers manual. My experience is I get the lightest consistent DA in a K frame (I haven't done much with L's yet) and I haven't done any firing pin in frame guns yet. I have done about 30 K frame's. With properly polished running surfaces in the lockwork, I've set K frame hammers to lift 46oz. with the factory calling for 56 oz. and had absolutely reliable ignition with Winchester primers. All guns vary and my 46oz. is just a guide, you will have to play with each and every gun. One of our forums very experienced gunsmiths takes the hammer to 42 oz. but he has some other non-published tricks he does. I use a 13lb. rebound spring in non-carry guns and leave the rebound spring stock in carry guns. All adjustments, per the factory, by grinding the strain screw. This is very pleasant work to do yielding very satisfactory (factory approved) results.
Illustrations are the Armorers manual. I hope I understood your question.

Stu

 

[Protocall_Design]

Lots of good information here. I use a trigger pull gage to check the hammer force. Then you can just read the number on the scale, and not limited to stacking and unstacking weights. The trigger pull gage may not be as dead accurate as weights, but it is repeatable if always using the same scale. As noted above, every gun is an entity unto itself. No 2 are exactly alike, although they can be very similar.

 

[RMFnLA]

This might get me banned from the forum, but back when I 'smithed I did lots of action work on S&Ws.

I did not have any way to measure mainspring "weight" so my test was a standard pencil. I would drop one eraser side down into a cocked revolver (unloaded, of course) and if the hammer fall was enough to pop the pencil completely out of the gun it passed.

Not very scientific, I know, but I did lots of action jobs and never had one come back because of light strikes (or for any other reason, for that matter).

 

[stansdds]

A word of caution when using the pencil test. It is best to use a pencil that has not been sharpened, otherwise you might be pulling the pencil out of the ceiling. Yes, I learned this the hard way.

 

[steelslaver]

While there are things you can do to lighten the pull, I believe that it is more important to have it real smooth. Get the high spots off the return slide and area it rides in, same with the stud bosses. No hard corners of problems with the hammer block. The cylinder turns easily on the yoke tube. Make sure the hammer and trigger don't rub the fame. The hand slips by the ratchet tooth right after lock up. A "tight" tooth tha locks up solid and the hand has to press by will cause a hitch right at the wrong time. Then, that lighter return spring will do its job, and so will a mainspring with less tension. (I do the shortened screw thing too).

Unless you have a weak trigger finger or grip a lb or 2 of DA trigger pull with a smooth trigger has little effect.

Becoming a better trigger puller is more effective than getting a perfect trigger. I effect my accuracy more than my worst S&W trigger does.

I do had a real hard trigger on anything. But, I really have a hard time with rough, hitchy pulls. I would rather have a smooth 12# double action pull than an 8# pull with a "spot" in it.

 

[chief38]

The slickest action I've ever had on any Smith is on my early 1950's vintage Combat Masterpiece (pre M15). It has a Target Hammer, Semi Target Trigger, W/O rear sight, R/R front sight and Trigger Stop . Single action pull is just about 2 lbs. and DA is about 8 - 8.5 lbs. PLEASE NOTE: This particular gun is ONLY used for competition shooting, bullseye and for fun. While I have NEVER had a FTF or malfunction with this Revolver, these spec's are NOT what I'd ever recommend for a Revolver to be used for SD, HD, CCW etc. My other Revolvers are smooth and less than Factory specs, but not to this extent as I do want them to be 100% reliable for SD.



PS: This revolver is dedicated to 148 grain WC's and sighted in at 6 o'clock hold. Super accurate!

 

[stu1ritter]

When it comes to double action trigger pull, smoothness is Job #1. Plain and simple. The lighter weight is only the whipped cream once it is reliable.

Stu

 

[Protocall_Design]

Most of my match guns are in the 6 to 6.5 pound DA range. A couple are 5 pound and a prototype one that starts at 6 and goes down to 3.5. These are all match competiton guns.

All my carry guns are smooth, but heavy. As chief38 says - DO NOT run a light trigger on a carry, self defense, or duty gun!!! If you need to use it, you won't even notice if it's a 20 pound trigger pull. You will have enough adrenaline going to pull any trigger.

 

[RMFnLA]

A word of caution when using the pencil test. It is best to use a pencil that has not been sharpened, otherwise you might be pulling the pencil out of the ceiling. Yes, I learned this the hard way.

Not only did this make me laugh it amazed me to learn that someone else uses this method; I honestly thought I was the only one!

Guess I won't be getting banned after all.

 

[chief38]

When it comes to double action trigger pull, smoothness is Job #1. Plain and simple. The lighter weight is only the whipped cream once it is reliable.

Stu

I TOTALLY AGREE! If I ever had a FTF after tuning (which I have not) I would not keep said gun in that condition. Guns that work 99% of the time are NOT my cup of tea and I'd never own one like that! I also test them with all brands of primers - as I would never have one that only worked with a certain brand. To me a gun should function 100% of the time with all brands of primers.

When I use to shoot SASS Matches I'd see a few of the guys who did their own action jobs that went too far and would routinely have misfires and would have to use only certain brands of primers - BAD!

 

[Roller Delayed]

I have not done anything on revolver triggers, but I "discovered" when I polished the trigger components on a 92 9mm pistol that the trigger pull weight decreased as the friction decreased. And I imagine that the primer impact actually increased as the hammer accelerates under less drag, so the mainspring weight could be effectively lowered by that additional amount.