While browsing through web sites on S&W springs, I saw a picture of a main spring that looked like it was extended or reversed. any ideas?
Reversed Main spring
- Thread starter jculloden
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For those who want a lighter than factory action, this is one way to get there. The object of the game is to get the hammer stirrup horizontal rather than at a 45 degree angle. Bending the mainspring in this configuration effectively shortens it. Doing this makes the trigger pull easier and makes the hammer have less downward pressure on the rebound slide, allowing the use of a lighter rebound spring. This works for K, L, and N frames, since they all use the same mainspring.
I came up with this many years ago. I don't know if anyone else has or not, as I have never seen it anywhere else. I'm not sure if this is what jculloden is referring to.
Edit to add - The 2 arrows in the 2nd pic are pointing to the corners you radius and polish to make the trigger rebound smoother and easier. One angled corner on the hammer and one 90 degree corner on the rebound slide that interact with each other.
I came up with this many years ago. I don't know if anyone else has or not, as I have never seen it anywhere else. I'm not sure if this is what jculloden is referring to.
Edit to add - The 2 arrows in the 2nd pic are pointing to the corners you radius and polish to make the trigger rebound smoother and easier. One angled corner on the hammer and one 90 degree corner on the rebound slide that interact with each other.
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Somehow that just doesn't look RIGHT. Doesn't mean it doesn't work.
It doesn't look normal, but you can't get different results by doing the same thing over and over.
It has worked really well on my guns. I don't post anything I haven't tried and verified.
It has worked really well on my guns. I don't post anything I haven't tried and verified.
JohnHL
Member
I would scarcely question your experience and abilities, being familiar with your numerous knowledgeable posts over the years.
But I would like to ask a question of clarification for my own education, if I may?
In the second picture with the modified mainspring, it looks as though the "hump-back" of the mainspring will contact the back strap when the hammer is cocked, thereby only flexing the upper portion of the spring.
I'm not reaching a conclusion, just wondering how it works.
John
The hammer being cocked pulls the spring forward. The "hammer down" position is as close as it ever gets to the grip frame. This is only a tiny fraction closer than the "at rest" position in the picture. It never contacts the grip frame if done correctly.
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JohnHL
Member
Then that is a very clever and resourceful way of improving a very common part.
My compliments to your observations and adaptations.
John
Thanks for the kind words, John. You may notice that I edited my answer in an effort to be more exact.
OP
Hi, That's the picture I was trying to find Thank You
OP
I'm going to try this today.......I'll report back on outcome
For those who want a lighter than factory action, this is one way to get there. The object of the game is to get the hammer stirrup horizontal rather than at a 45 degree angle. Bending the mainspring in this configuration effectively shortens it. Doing this makes the trigger pull easier and makes the hammer have less downward pressure on the rebound slide, allowing the use of a lighter rebound spring. This works for K, L, and N frames, since they all use the same mainspring.
I came up with this many years ago. I don't know if anyone else has or not, as I have never seen it anywhere else. I'm not sure if this is what jculloden is referring to.
cgt4570
Member
There was also a 'W' shaped mainspring used in target guns (mostly N's) for a very short time in the 1950's. Of all the unusual S&W stuff I have, I haven't been able to find one of those.
I have one. It doesn't work very well. You are not missing anything.
Where can I get a couple so I can try them out?
In a weird way, those pics make me think this modification effectively shortens the mainspring. The entire spring from the strain screw up has to flex normally. By bending it so the top portion is in line with the direction of travel, that portion of the spring doesn’t have to flex anymore - only the shorter portion below the bend flexes.
I brought that up because I’m trying to understand what is happening here. Also if I’m correct, then you could adjust the amount of change by where that first, lower bend toward the backstrap is.
Do you need to heat the spring to bend it or heat treat afterward?
I brought that up because I’m trying to understand what is happening here. Also if I’m correct, then you could adjust the amount of change by where that first, lower bend toward the backstrap is.
Do you need to heat the spring to bend it or heat treat afterward?
This mod does effectively shorten the mainspring. That is in the original post.
The top part still flexes some, because the spring gets stiffer as it goes down. The whole spring flexes together this way more than the original way.
The bottom bend in this example could be slightly more. That would move the top bend forward to give a bit more clearance of the back strap to the top bend.
In the original setup, the spring is in a little bit of a bind, because it is partly getting bent towards the bottom of the spring. This makes it harder to bend, therefore harder to pull the trigger. Most of the bending is just in the top half of the spring.
The "new" way allows the spring to only go front to back and allows the spring to naturally bend along the whole length, getting progressively stiffer as it goes down the length. That makes it easier to pull the trigger for the same spring tension on the hammer.
These are very high quality springs. They have the right alloy and perfect temper. They do not need to be heated to make the bends, nor heated afterwards. Because of the right temper, they will stay where you bend them indefinitely. You need to make sure that all bends are a large, smooth radius to avoid having stress risers in the spring.
You will need a different strain screw for this spring. I use a #8-32 x 3/8" long for RB and a 1/2" long for SB grip frames. You will need to use either purple #222 or blue #242 Loctite to hold them in place, yet still be adjustable. Coat the threads well and wipe off the excess. One drop isn't enough.
I make a small access hole in the grip for easy tuning at the range. All my guns are working guns, so I'm not overly concerned about them looking pristine.
The top part still flexes some, because the spring gets stiffer as it goes down. The whole spring flexes together this way more than the original way.
The bottom bend in this example could be slightly more. That would move the top bend forward to give a bit more clearance of the back strap to the top bend.
In the original setup, the spring is in a little bit of a bind, because it is partly getting bent towards the bottom of the spring. This makes it harder to bend, therefore harder to pull the trigger. Most of the bending is just in the top half of the spring.
The "new" way allows the spring to only go front to back and allows the spring to naturally bend along the whole length, getting progressively stiffer as it goes down the length. That makes it easier to pull the trigger for the same spring tension on the hammer.
These are very high quality springs. They have the right alloy and perfect temper. They do not need to be heated to make the bends, nor heated afterwards. Because of the right temper, they will stay where you bend them indefinitely. You need to make sure that all bends are a large, smooth radius to avoid having stress risers in the spring.
You will need a different strain screw for this spring. I use a #8-32 x 3/8" long for RB and a 1/2" long for SB grip frames. You will need to use either purple #222 or blue #242 Loctite to hold them in place, yet still be adjustable. Coat the threads well and wipe off the excess. One drop isn't enough.
I make a small access hole in the grip for easy tuning at the range. All my guns are working guns, so I'm not overly concerned about them looking pristine.
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Im thinking someone was messing around with their revolver and unknowingly replaced the mainspring backwards. They were so proud of their “action job” they began to show it off before realizing their mistake. So… in defense of looking foolish they decided to convince others they had “out engineered” the engineers and had come upon a revelation that would change how kitchen table action jobs were done in the future! On a more serious note, my armorer school instructor - Don Dion, told our class that having a screw to install a revolver mainspring instead of how Colt mainsprings are installed was a big mistake and the factory had spent untold hours “fixing” guns that were having action issues and light primer indent. He said “if there was a screw on a gun then guys will turn the screw”.
You make your own out of a regular mainspring. If, for any reason, you decide it's not for you, it only takes a few minutes to go back to original. You are not changing or altering the gun, just one mainspring. Don't worry, you can't put it in backwards as some seem to think.
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I have never used a mainspring that was not a factory original - absolutely no need to! All I've ever done is to swap out the rebound slide spring to a lighter one and to slightly shorten the main spring strain screw. I do not keep it loose - I actually shorten it a tiny bit. They are cheap enough and if one ever gets too short by accident (rarely happens because I have done this many times, am careful and go slowly), I toss it and use a new one. I have gotten good enough at this that I no longer even need a trigger pull scale, I just go by feel now. This gives me a crisp and smooth 2.75 - 3 pound single action pull and about an 8- 8.25 pound double action pull. That's about as low as I feel is ok to go for reliability but still makes shooting easy.
I would also suggest testing your lightening job with the hardest primers to set off. Those seem to be CCI brand. I have never had one fail to go bang and the dent left in the primer is proper. If you have even one FTF, you are too light! I don't believe in changing primers or ammo to justify a too light trigger pull.
PS: I always keep the original screw and rebound spring in the original box with a note regarding what it is. They always get reinstalled if I sell, gift or trade a gun.
I would also suggest testing your lightening job with the hardest primers to set off. Those seem to be CCI brand. I have never had one fail to go bang and the dent left in the primer is proper. If you have even one FTF, you are too light! I don't believe in changing primers or ammo to justify a too light trigger pull.
PS: I always keep the original screw and rebound spring in the original box with a note regarding what it is. They always get reinstalled if I sell, gift or trade a gun.
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I think there's room for everyone - Those who stick to what they know, and those who like to try new things.
There is nothing dangerous here, like going to the bottom of the ocean in a submarine. This is one of those things that can't hurt, might help. No harm in giving it a try. Anyone who wants to, can try it, anyone who doesn't want to, doesn't have to.
I do feel sad for those who go through life afraid to try anything new or different, though. Life is what you make it. I'm making mine a fun adventure.
There is nothing dangerous here, like going to the bottom of the ocean in a submarine. This is one of those things that can't hurt, might help. No harm in giving it a try. Anyone who wants to, can try it, anyone who doesn't want to, doesn't have to.
I do feel sad for those who go through life afraid to try anything new or different, though. Life is what you make it. I'm making mine a fun adventure.
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Protocall Design, You are spot-on! I always chuckle at some of the fellas who parrot the factory montra saying only what the Factory says is correct and proper for everyone in every case scenario. The Factory is not concerned about the trigger pull being so heavy one can not effectively shoot or compete in a descent fashion, they are only concerned about being ridiculed, sued, and demonized. HEY, their own professional shooters like Jerry Miculek only competes and sets records with finely tweaked and refined guns!! To me that's saying, "do what I say, not as I do"!
I am old enough and have enough experience (over 45 years with S&W revolvers) with many forms of shooting and competition, long range sessions and pretty much using every brand ammo available (including hundreds of thousands of reloads that I have made) to know what works and what doesn't. There are some "keyboard commando's" who barely shoot but they will be the first to quote what the Factory will say for liability purposes. That doesn't bother me in the least as I've been there - done that and know when to stop.
I have never had any firearm with a hair trigger, I've never had one that failed to set off a primer, regardless of brand and how hard they were, and never try and substitute an ultra light trigger for the ability to shoot well. This has come with experience of trial and error. My carry gun for decades was a M60-7 which I actually left stock just as it was built. I never wanted to have any issues in a court of law if I had never needed it in a SD situation - luckily I never had to use it. Because it was on the heavy side I practiced with it very often which did two thing..... it trained me to shoot it well as is and it did wear in to some extent. Target only guns are a different animal in my opinion. As long as I risked only loosing a match and not my life, I was OK with trying different things. Again, I learned quickly how far was too far. That is also another very important factor - one needs to understand and accept that.
I am not the smartest man in the world nor am I a factory certified gunsmith - never said I was. That said, after 45 years of doing this, shooting many hundreds and hundreds of thousands of rounds over those years, I know what works, what is safe and how far too far is.
Up until two years ago I collected, ran and enjoyed Lionel Electric Trains. I never worked for the Company, I never worked in a Train store, but I'd routinely repair and improve their locomotive, accessory's and rolling stock designs to make them run and operate correctly when their own engineers could not. At one point I even did repair work for one of the largest Train Stores in the Country! Never had an engineering degree or certificate that I went through "Lionel School" which they actually did have BTW.
Summing it all up, COMMON SENSE trumps everything IMHO. Knowing what is good and when to stop is another equal part of the equation.
