Downside to clipping stock rebound spring?

[Cherokeewind]

What is the downside to clipping a stock S&W rebound spring to yield about 3 pounds of pull on the rebound spring alone?

Thanks.

[Waltermitty]

By itself, no downside, but if everything else isn't correct, the gun won't reset. Then you'll have to buy a new spring ?

 

[Alaskan454]

Go buy a 3 pack of lighter Wolff springs after you get the mainspring to 100% reliability.  You can alter the rebound to your liking and will have extras in case you go too far.  If everything else is polished 3# should be okay, but you might want to start a little higher.

[Waltermitty]

Search "Trigger job Randy Lee". Then read to learn grasshopper. 

[Toolguy]

The length of the spring is important. There is a point (of length) at which the spring won't rebound whether it's a factory one or a different one. I think you are better off going with a lighter one, then if you want to clip it some, it will still be longer at a given spring pressure than a factory one. 

[Cherokeewind]

Thanks for the replies.....

I have about a dozen "light" rebound springs, from 12 to 16 pounds.  Also have clipped enough stock springs to understand that one can get the stock spring short enough that it runs out of "umph" just before the trigger is fully reset.

I have my 686 set to 6# with 3# on the rebound spring.  When set to 5# (with about 2.5# on a clipped factory rebound spring), I found that I wasn't getting the snappy reset that I like.

[Toolguy]

I'm working on a spring kit that will address these issues. It's a development project, I'm not sure when it will be done. I don't want to send anything half baked out the door though.

[Distant Thunder]

1 hour ago, Toolguy said:

I'm working on a spring kit that will address these issues. It's a development project, I'm not sure when it will be done. I don't want to send anything half baked out the door though.

 

Somehow I don't see something half baked coming from you as a big worry on our part. Let us know when the kit is ready for prime time. I'm guessing this will be available for both K/L and N frame models?

[Toolguy]

Yes, It will work for K,L, and N frame.

[practical_man]

I will happily sign of for a kit from you!  

[johnmac]

On 10/18/2016 at 8:52 PM, Cherokeewind said:

What is the downside to clipping a stock S&W rebound spring to yield about 3 pounds of pull on the rebound spring alone?

Thanks.

Downside of a shortened rebound spring is a choppy trigger pull in my experience.  Get the lightened spring of the proper length for superior results. 

[pete627]

On 10/18/2016 at 5:52 PM, Cherokeewind said:

What is the downside to clipping a stock S&W rebound spring to yield about 3 pounds of pull on the rebound spring alone?

 

Brownells has a pack of 10 - 11lb wolf rebound springs (their item number - 969-000-033WB) for $16 or so. I can't find my pull weights anymore for just the rebound by itself but old notes say that an unmolested 11 pounder was similar (my measurement)  to the Apex medium spring (.165 wire diameter ... that came with an N frame hammer kit).

I ended up cutting two coils off an 11 pounder (as someone else recommended ... that was over 6000 rounds ago ... need to go back in soon and see if the "Apex light spring (.160) will work now ... it was significantly lighter but the gun was still a little too rough at the time to get away with it). 

The cut 11 pounder worked so good ... I made up a few extra ... putting one in my model 10 a friends model 19 and another friends N frame (swapped out for unmolested 11 pounders that we had already installed from the original package).  

[RePete]

I've had success clipping off no more than 1 1/2 coils from the factory spring.  Zero issues.

Learned from my PPC days, a 14# Wolffe rebound spring will give a 2 1/2# SA pull.

[toothguy]

2 hours ago, RePete said:

I've had success clipping off no more than 1 1/2 coils from the factory spring.  Zero issues.

Learned from my PPC days, a 14# Wolffe rebound spring will give a 2 1/2# SA pull.

For PPC you're working to hard, that's probably around a 7.5 to 8 lb DA pull.   for PPC you don't need a great snap back and your score will improve if you shoot DA.  You can easily take at least a pound off your trigger pull by using an 11 lb rebound spring and cut off 2-3 coils.  If the top of the rebound slide is polished well you can get sufficient, balanced return for PPC.

[RePete]

53 minutes ago, toothguy said:

For PPC you're working to hard, that's probably around a 7.5 to 8 lb DA pull.   for PPC you don't need a great snap back and your score will improve if you shoot DA.  You can easily take at least a pound off your trigger pull by using an 11 lb rebound spring and cut off 2-3 coils.  If the top of the rebound slide is polished well you can get sufficient, balanced return for PPC.

FYI:

I use the factory mainspring, internal moving parts polished and I shot DA only.  The trigger pull gets reduced with the rebound spring, albeit a little, but when Federal primers were not available, I could set off CCI's.

 

I did use the Wolfe Power Rib for a year, but I didn't like the feel and sometimes a FTF condition occured.

[toothguy]

29 minutes ago, RePete said:

FYI:

I use the factory mainspring, internal moving parts polished and I shot DA only.  The trigger pull gets reduced with the rebound spring, albeit a little, but when Federal primers were not available, I could set off CCI's.

 

I did use the Wolfe Power Rib for a year, but I didn't like the feel and sometimes a FTF condition occured.

I have never use CCI primers because Winchester primers were always available when nothing else was.  For my carry gun I used the Miculeck hammer spring with an 11 lb rebound spring (full length).  This gives a little less than a 7 lb trigger, with good snap back, that sets off Winchester primers and all the factory ammo I have run through it.

Edited October 28, 2016 by toothguy

[Alaskan454]

My 625 will set-off any brand of primer at around 7.5 lbs using an unmodified 11# rebound and Wolff mainspring.  The CCI primers are so darn picky though, I can drop it to 7 lbs and it will pop 99 of them, but not 100.  After I'm done with my current supply I will never buy CCI again, Winchester primers have been great and are much more forgiving in hammer force.

[RePete]

You are lucky, but where I am, Canada, primers are not as plentiful.  

 

Win primers have been crap, a lot of misfires in autos as well as revolvers.  I have had good luck with Remingtons though, when I can get them.

[VanMan1961]

clipping off coils to shorten the rebound spring will reduce the "pre-load" on the spring, but will not have any effect on the rated compression rate of the spring.  It's been a while since my mechanical engineering classes, but it goes something like this.

• A "15 lb" spring would nominally increase 15lbs of resistance force for each inch compressed. 
• If it was compressed .200" during installation, it has a pre-load of 3lbs. 
• It will increase 1.5 lb in resistance for each .100" compressed,
• assuming .500" compression, it will increase by 7.5lbs to a net of 10.5lbs

Here's an example comparing a 15lb spring, a 15lb spring cut down so the initial compression is only .100", and a 11lb spring.  (note these are just examples.  I don't have the specifications for the actual S&W rebound springs)

So compared to the cut down 15lb spring, the 11lb spring has the advantage of higher preload (more positive trigger reset) and a lower incremental resistance for distance compressed to a lower net resistance force.

 

 

 

Edited October 29, 2016 by VanMan1961

[RePete]

IIRC the factory rebound spring is 17#.

[Cherokeewind]

VanMan1961, 

Thanks---this I can understand:)  It puts numbers to what I observed/experienced when I clipped the factory springs.