Reduced mainspring in S&W 617?

[AndABeer]

Picked up a 617 the other day from a friend looking to divest. It was practically NIB. Shot it for the first time Friday. What a fun .22!!!

Has anyone out there ever put a reduced mainspring in one? I generally do this to all my S&W revolvers with no problems but they are all centerfires. Should I be concerned about light strikes with this rimfire?

 

[C.R.Sam]

I have had good luck with slightly reduced hammer spring.

I have gotten more drastic results by reducing the trigger rebound spring. Blending the edges and buffing the rebound block usually makes a noticible difference.

Just plain shootin it also makes it go from very nice to fallinlovewith nice.

Have done the above to several 17s. Two of which were good enough to go head to head with Pardinis, Hammerlis, Walthers etc.

Sam....Wonderful day, got up and had a pulse.

 

[Mike Irwin]

Unfortunatly, this is a big MAYBE.

Friend of mine got a 34, and it was not reliable in double action. Single action was fine, but double would, depending on the ammo, cause about 20% fail-to-fire.

I took a look at the spring, and it was clear that someone had lopped off some coils. No problem. We order a Wolff kit, which I install.

Better, but we're still getting about 10% fail-to-fire.

So, I dropped a factory mainspring in for him. 100% reliable with all ammo.

I probably could have worked the gun's internals to make it reliable with the reduced power Wolff, but he said it would be easier just to go with the factory mainspring.

I agree with CR, the rebound slide spring will give you a big reduction right off the bat.

And you know, I really hate agreeing with CR...

 

[mikey357]

Mike Irwin makes a good point, as far as it goes...S&W actually makes a different, slightly STRONGER mainsring for the J-frame .22's than for the centerfire J-frames...this is NOT the case for the K-frame .22's...in other words, the K-frame .22's use the SAME mainspring as all other K-frames. I have a K-22 "CH" that has had a PRIMO action job done...DA pull weight about 7&1/2 lbs...and its completely reliable with any ammo I have yet to put thru it!!! If you try an aftermarket "reduced-power" mainspring and it DOES compromise reliability, just put the stock m'spring back in. A trick I have used in the past with S&W revos that have NOT liked the reduced-power mainsprings is to get a Wolff std.-power m'spring and reduce the tension by leaving the revo "Cocked" in SA mode for a period of time...in one Model 686 Plus, that reduced the DA triggerpull from 10&1/2 lbs to 9 & 1/4 lbs...took several days, though, with the revo LEFT at full cock. This revo WOULD'NT work with the Wolff reduced-power m'spring...took the DA pull down to about 8 lbs, which wasn't 100% reliable. Just another idea-or two-FWIW....mikey357

 

[mikey357]

Just an addendum to my previous post...looking at my notes, I see that the "leaving it at full-cock" trick has reduced the DA triggerpull anywhere from 1/2lb to 1&1/2, DEPENDING on whether the mainsping tension screw was stock or not AND how long the revo was left at "full-cock". Average reduction was around 1/2lb to 3/4lb...speaking of the mainspring tension screw, IMHO it is NOT a good idea to back it out to try to reduce the DA trigger pull weight...seems that when I do that, it'll eventually back out MORE than I want it, on its own...much better to either use a reduced-power mainspring OR CAREFULLY cut down the tension screw...a little at a time!!!....mikey357

 

[MADISON]

Weaker Mainspring?

There is no reason rimfire and centerfire sould not be the same.

I would get a "weaker" mainspring and a "factory" one. If a kit of heavy, factory and, light were available that is what to get. Don't forget the "TRIGGER RETURN SPRING".

 

[sw627pc]

Well I don't know about a 617, but I tried the Wolff reduced springs in two five screw K-22 guns and had to go back to the original springs. Problem wasn't ignition. Triggers got so light that SA was dangerous (one would fire if the gun was jarred a bit). I did note that there was a difference not only in weight, but length and shape between these gun's springs and the Wolff springs. My five screw Military and Police had no problem, but apparently old K-22's had something slightly different.

 

[AndABeer]

Just back from the range with the new reduced springs in. The trigger pull was much improved, but I had two ignition failures out of 100 rounds. Not too bad and the ammo was Remmy bulk box so it may have been that.

 

[mikey357]

If I remember correctly, Wolff usually puts a 13, 14 and 15 lb. rebound spring in the S&W "spring kits". The stock rebound spring is an 18-pounder. I have found that I prefer the "feel" of the revolver with the 15 or 16 lb. spring...even tho' I had to order the 16-pounders seperately. FWIW, it seems like a one-pound change in the strength of the recoil spring-by itself-will change the SA trigger pull about one-quarter of a pound...and remember, YMMV....mikey357