M66, 686+ springs interchangeable?

[Guy B. Meredith]

Title says it all. Can the mainspring and trigger rebound spring from a 686+ be put into a M66 K-frame? My 686+ is like butter, my M66 is not. Reading about performance replacement springs makes me leery about needing other than WPS primers to get consistent ignition.

My 686+ goes bang every time so I assume I would have no worries if the springs can be used in the M66.

 

[Guy B. Meredith]

Just got my answer by checking out Wolff website. Comments there make me wonder whether I should go ahead and try their springs.

 

[straightshooterjake]

To directly answer your question, yes, the springs from a K-frame (model 66) are interchangeable with the springs from an L-frame (model 686). However, getting a good trigger pull that is reliable with all types of primers usually involves more than just swapping springs.

For most people who want to improve the trigger on a Smith & Wesson revolver, I recommend looking for a gunsmith who has some expertise with revolvers. If you would prefer to learn more about this subject yourself, I have written a long article about working with the triggers on S&W revolvers.

The article is here:

Improving the trigger on Smith & Wesson Revolvers

The article is also discussed in this thread:

https://www.thehighroad.org/index.p...wesson-revolver-triggers-please-review.817407

 

[RON in PA]

Do you have a new 66 or an old one? If new don't change anything until you have put at least a thousand rounds thru it. New Smiths need a breaking period to smooth things out. Also realize that no K frame will have the trigger pull of a L frame. When S&W came out with the 586/686 in 1980-81 they made minor design changes so that the DA pull was subtlety improved over the K frame.

 

[GRIZ22]

Is your trigger feel gritty or too heavy? Many confuse smooth and light. A smooth trigger is not necessarily light and vice versa.

Smooth is more important than light. It's achieved by how the components of the mechanism mesh. It can be achieved by wearing in or more precise fitting (an action job).

You can swap out springs and you will have a lighter, still gritty trigger. Springs affect ignition, functioning, and trigger pull in a revolver. If you "improve" one it affects the other two. It is interesting to note I've read Miculek uses extra power springs in the revolvers he uses for fast shooting demonstrations. I'm sure his triggers are smooth. This ensures reliability and functioning while giving a heavier trigger. A heavier trigger can be dealt with by improving the muscles involved pulling it.

 

[reddog81]

I'd just buy a spring kit and test that out rather than playing musical chairs with the current springs.

The trigger return spring has no effect on primer ignition (if you already knew this, please forgive me). I recently swapped out the stock trigger return spring for the middle weight spring from the Wolff pack and it dropped the trigger from over 11 lbs to close to 9.5 lbs just from that one modification. The light weight mainspring brought the double action pull down another 2 lbs, but resulted in frequent misfires. I have purchased the regular Wolff standard power mainspring also, but haven't tried it yet to see if there is any difference.

 

[Guy B. Meredith]

Thanks for the replies. For some reason I am not getting notices of your responses so I haven't checked here in a while.

What were the changes in the trigger improvement changes in the 686?

I'm going to have to get the 686+ out of the safe and do some careful comparison. To my immediate memory, the 686+ does feel a bit lighter but is just very smooth. I really feel like I am moving a heavy object on the M66. Could be that the action still hasn't smoothed out.

The 686+ probably has over 35K rounds through it. Not sure as I was using the PC627 for a while. The M66 has definitely had over 1000 rounds through it.

 

[straightshooterjake]

A well tuned K-frame (model 66) can have an excellent trigger. I am not aware of changes to the L-frame (model 686) to improve the trigger pull. There may be changes that I have not heard of that improve the trigger in the L-frame, but the primary reason the L-frame was developed was to create a beefier gun that could withstand a steady diet of .357 magnum loads. Also, the actual triggers are the same between a K-frame and an L-frame, only the hammers are a different size. So any changes in geometry are pretty minor.

If you have a K-frame with an unsatisfactory trigger, then it is an excellent candidate for a quality trigger job.

If you are interested in a trigger job, then the article I linked to above contains lots more information. It discusses changing springs vs polishing parts, and it will help you determine whether to do it yourself or whether a gunsmith will add value.

Good luck. You have some great guns, and they are both capable of having triggers that meet your needs.

 

[reddog81]

The difference between the triggers is because every single gun is unique. The J Frame uses a completely different spring setup, and i'm not sure about the X Frame, but the K, L, and N frame setups are basically the same. Any trigger improvements or distinctions apply across the board. The setup has had minor tweaks every couple of decades but the insides of a 10 year old gun look surprisingly similar to a 100 year old gun.