Installing weaker springs in a revolver

[Molon Labe]

(Note: I first posted this in THR's Handguns: Revolvers forum, but did not receive any responses. Perhaps I'll have better luck here.)


For Christmas I bought my wife a Taurus model 651 5-shot revolver in .357. (This model is very similar to the Taurus model 605, and most internal parts are interchangeable between the two models.) The gun is very nice, but she said the trigger force was too high.

So I looked into installing some lighter springs. W.C. Wolff Co. sells the following replacement springs for the 605/651 revolvers:

Hammer Spring (Mainspring)
Reduced Power: 9 Lb. (factory is 11 lbs.)

Trigger Return Spring
Reduced Power: 6.5 (factory is 14 lbs.)

Trigger Return Spring
Reduced Power: 9 Lb. (factory is 14 lbs.)

I purchased a kit from Wolff that contained all three springs. After disassembling the gun I did the following:

1. I removed the 11 lb. factory hammer spring and installed the 9 lb. Wolff hammer spring.

2. I removed the 14 lb. factory trigger return spring and installed the 6.5 lb. Wolff trigger return spring.

After reassembling the gun, I test fired it in the backyard using Federal .38 FMJ. About 20% of the time the round "hangfired," which means the firing pin hit the primer but the round did not go off.

There's no doubt that the problem is due to the lighter springs. So what should I do? Should I remove the 6.5 lb. Wolff trigger return spring and install the 9 lb. Wolff trigger return spring? Should I remove the 9 lb. Wolff hammer spring and install the 11 lb. factory hammer spring? Or should I reinstall the both factory springs?

Thank you

 

[HSMITH]

Try leaving the trigger return spring in and put the factory mainspring back in, the trigger return spring does not affect how hard the primer is hit. Only the mainspring affects the hitting force.

 

[stans]

This is pretty common with light weight springs in double action revolvers. The mainspring is now light enough that in double action it does not impart enough energy into the hammer to fire a primer. It is less of a problem in single action since the hammer is pulled back further to engage the single action cocking shelf. Put the factory hammer spring back into the revolver and it should shoot just fine in single and double action. The trigger pull will be just slightly heavier, but the improvement in reliability is worth it.

 

[4v50 Gary]

Concur. There was no need to change the hammer (main) spring. That spring provides the forward energy for the hammer and if weak, you'll get misfires/hangfires. Replacing the trigger spring is OK, but the return of the trigger to its position of rest when released may be sluggish. That's the trade-off you get for a lighter trigger. But if it works for the wife and she masters the gun, then all the better.

However, get her one of those grip squeezer balls to develop her grip strength. That's the best solution and it doesn't affect the gun.

 

[Molon Labe]

So if I understand correctly, it is O.K. to install a weaker trigger spring (e.g. 6.5 lb vs. the factory 14 lb.), but I should not change out the hammer spring?

And what benefit will I get from installing a weaker trigger spring? Will it be easier to squeeze the trigger?

Thanks

 

[Jim Watson]

Well, you have the stuff, I'd try all possible combinations.
Yes, a weaker trigger return spring will make it easier to squeeze the trigger, but you should not use one so weak that your trigger finger can outrun it as it resets. Or worse, binds and doesn't reset at all.

I suspect you will end up with the factory mainspring and the 9lb trigger spring, or maybe factory throughout, but no reason not to try the other setups.

Federal primers are the most sensitive on the market, and if they don't go off, you have MUCH too little mainspring.

By the way, what you have is 20% *misfires*.
A "hangfire" is when the gun goes off but after a perceptable delay. Very rare with modern ammo, but there used to be all sorts of warnings about them, to leave the action closed for 30 seconds after a round fails to go off so you wouldn't have the action open when it finally blew. I have had one, ever, in 35 years of pretty steady shooting, and it was a matter of a second or less.

 

[Jim K]

Just something to consider. Gun makers build in a certain leeway for adverse conditions. Revolver springs are made strong enough to ensure funtioning in cold, dust, wet, etc. When a spring is replaced with a weaker one, even if the gun works on the range, part of that extra margin is removed and the gun may not work if it is dirty or cold. Note that "dirty" does not necessarily mean in a howling sandstorm. The gun could be dropped in dirt or water. Pocket lint can cause a gun to malfunction, as could the normal "debris" from a purse. (OK, OK, your wife's purse is spotlessly clean - my wife's sure isn't, but don't tell her I said that.)

Jim

 

[OH25shooter]

FWIW: I had a gunsmith do a complete trigger job on my S&W 686. Nice and smooth, but I was having to many FTF. So, he reinstalled (removed the Wolff spring) the factory main spring back into the revolver. That solved the FTF problem. It's still noticably smooth since the internals were cleaned up. And I'm comfortable knowing the gun will fire when the trigger is pulled.

 

[JNewell]

Jim K's points are really worth noting. If the gun has to go bang on demand, put the factory springs back in. Substituting mainsprings can result in failures to fire. Substituting trigger reset springs can result in failures to reset and/or jams. I've been down this path before and had problems every time. All of my revolvers have factory springs in them as a result.

I think we often fail to give the engineers who design these guns enough credit...but ymmv, it's your gun.

 

[tbeb]

Molon Labe,

My wife's hand and trigger finger is not very strong. Her Ruger Speed Six has a double action trigger pull of about
8-lbs., which is light. Custom work had been done by the previous owner. Revolver has never misfired. I use ammo with Federal primers in my self defense revolvers, because they are the "softest". Point is that you can get a trigger pull light enough for your wife and still get reliable ignition.

A retired west coast police officer told me officer's in his department had to be able to rapid fire a revolver in double action mode 12 straight times. If they couldn't they did exercises to strengthen their grip. Someone suggested squeezing a tennis ball and that is good advice.

 

[PzGren]

I had a problem with a S&W M15 due to a lighter triiger return/rebound spring.
After changing to a lighter spring, the trigger did not return always but stayed back every 20 times that I pulled the trigger.
After polishing the rebound slide and the interior hole, where the spring is, I had reliability back again.

I would recommend to let your wife start dry firing the revolver with the reduced power springs and then move the spring weights back up.

 

[Standing Wolf]

...what benefit will I get from installing a weaker trigger spring? Will it be easier to squeeze the trigger?

It should be, but there are no guarantees with revolvers and springs.

After polishing the rebound slide and the interior hole, where the spring is, I had reliability back again.

That five-minute operation can shave up to a pound off a revolver's single action pull, as well as make the pull feel much less sticky.

 

[grey9551]

Trigger job

Before changing out the springs do a trigger job. If you are unable to do a trigger job dry fire the weapon a few hundred times to smooth things out. Make sure all the parts are cleaned up. Put it all back together and see if you even need to change springs.

If the trigger pull is still to high you could try changing out the springs and getting a little longer firing pin and see if that helps. If not then either you or a smith you trust will have to do the trigger job and when doing it remember it is easier to take more off than it is to add metal back so just go very slow.

Before you reassemble the revolver make sure all the grit is off all parts and internal surfaces. I would first stick the stock firing pin back in. I would put in the lighter hammer spring and the lighter trigger rebound spring and leave the main spring original.

It should be reliable now try it out and see and then by a box of ammo with federal primers and see how they work. I would change the mainspring as a last resort in a Taurus.

Gary

 

[Standing Wolf]

I believe this is worth adding: if it's a carry gun and you've done anything to the springs, put at least a hundred rounds through it without any failures to fire before carrying the gun. Anything less than absolute reliability in a carry gun or bullseye match pistol is completely unacceptable.

 

[Molon Labe]

Thanks for the advice, everyone (especially Jim Keenan & JNewell). The gun will be a self defense / CCW piece, and reliability is critical. I am thus going to reinstall the factory springs.

Which brings me to another question: why are weaker springs available from Wolff (and others)? When/why would a person install weaker springs in a gun? Would it be done as part of a custom trigger job, perhaps?

 

[P95Carry]

I played with reduced poundage springs years ago - tried a reduced leaf in a Smith, reduce mainspring in a Redhawk .. and others I have forgotten.

End result was invariably same ... even with Fed primers. Some loss of reliability. For PPC compo's etc - it was useful even tho occasional FTF's ... but if carry is in the frame then no - and no ... not good.

I prefer a smooth trigger with no creep and perhaps a tad heavy - to one with a lighter poundage but poor feel. So smoothness wins for me ... reliability too. Essential.

 

[Standing Wolf]

When/why would a person install weaker springs in a gun? Would it be done as part of a custom trigger job, perhaps?

On the whole, lighter trigger pulls enhance accuracy.

 

[JNewell]

On the whole, lighter trigger pulls enhance accuracy.

I think that's one of the reasons, but if you practice DA shooting a lot, strengthening your muscles and developing your technique, it will not matter. IMO, YMMV, etc.

 

[BluesBear]

Some revolvers willwork with the reduced powert sprimgs and some won't. It all depends on the gun.

However a 2 pound reduction isn't really all that severe. You can install a spacer at the bottom of the mainspring to increase thew power of the hammer fall.

Usually though the reduced trigger return spring will reduce the trigger pull to acceptable levels. Just make sure you get sufficient trigger return for rapid firing. If you get ANY hesitation whatsoever the spring is too light.



Also as has been said before and hangfire is a delayed detonation usually caused by contaminated powder. I call them a fizzbang because in some recent surplus .303 British I have encountered you can hear a slight "fizzing" or "sizzle" for a little less than one second before you get that BANG!

A round that won't fire at all is a dud.

 

[Standing Wolf]

I think that's one of the reasons, but if you practice DA shooting a lot, strengthening your muscles and developing your technique, it will not matter.

Doesn't do the trick for arthritic hands.