Main spring replacement

[SLT223]

I have 1975, 27-2, 5" with a tired main spring. It's actually kinked at the strain screw (not by me...was like that when I got it). Does S&W still make a correct main spring, do I need to locate, an NOS unit, is there a go-to after market spring?

 

[Hapworth]

S&W I believe can supply a new mainspring, though they are moving slow at present with various work and parts orders.

Personally, I'd go to Numrich's site and order one.

If you're interested in aftermarket, Wolff is by far the way to go -- a Type 1 Standard Power mainspring, unless you intend to go reduced power, which has various caveats.

 

[O2Guy]

If you're a shooter, go with the Wolff spring. You won't be disappointed.

 

[raytsmith]

Be advised - sometimes Wolff springs require a longer strain screw to work. On newer guns, a Wolff spring will cause the rebound slide to hit the mainspring unless you put in a longer screw, because the channel that the 'power rib' forms extends down to where the screw makes contact, and it doesn't flex the spring enough.
The Chip McCormack springs that I've seen do not have this channel and might be a safer bet. I'd go with a factory spring, though, if you can find one.

 

[steamloco76]

Be advised - sometimes Wolff springs require a longer strain screw to work. On newer guns, a Wolff spring will cause the rebound slide to hit the mainspring unless you put in a longer screw, because the channel that the 'power rib' forms extends down to where the screw makes contact, and it doesn't flex the spring enough.
The Chip McCormack springs that I've seen do not have this channel and might be a safer bet. I'd go with a factory spring, though, if you can find one.

Put a fired small pistol or small rifle primer over the end of the strain screw if the screw is too short for a Wolff spring. I have Wolff springs in several Smiths including a pre-model 10 and a 28-2. Have experienced zero problems and have not needed a longer strain screw or the primer screw extension fix.

 

[glenncal1]

If you're a shooter, go with the Wolff spring. You won't be disappointed.

+1 I put a Wolff mainspring in a K-22 OD that was having major FTFire issues, all solved. Trigger feels great.

 

[ken158]

I have a few factory springs I bought when a local shop went out of business.... send me a PM if interested.

 

[kaaskop49]

Wolff caveat?

I installed a Wolff mainspring in an old 1915 (formerly .455) revolver and was unable to cock the gun for SA firing, altho DA was ok. I swapped springs with a modern N frame and now both guns are fine.

 

[KLYDE]

I recently purchased a very nice 625-4. I could tell do to the light action that it was sporting a Wolf mainspring. Trigger return was also way too light for my liking. I broke down the gun and replaced the cylinder stop, rebound spring and main spring with Factory units. The action is now spot on. I'd replace with Factory.

 

[tlay]

Are you sure of the mainspring? A lot of the mainsprings do have a bend near the screw. Is the strain screw tight? All the way down? Can you take a picture of it and post it?