When to change hammer springs

[Johnny Swan, SASS #50322]

How many rounds do you run on 15 lb Wolff springs before you change them. Springs are on NMV

[The Original Lumpy Gritz]

Thousands 

[Garrison Joe, SASS #60708]

I run 1911s with many more rounds than any of my revolvers, and I change the mainspring (hammer is driven by the mainspring in that gun) at about 50 thousand rounds.   Good coil springs last for many many cycles.

 

Have never changed a revolver spring except to go to a lighter spring when tuning the action.

 

Flat springs like in the 1873 rifle are much shorter lived.

 

good luck, GJ

 

 

[Dusty Devil Dale]

56 minutes ago, Garrison Joe, SASS #60708 said:

I run 1911s with many more rounds than any of my revolvers, and I change the mainspring (hammer is driven by the mainspring in that gun) at about 50 thousand rounds.   Good coil springs last for many many cycles.

 

Have never changed a revolver spring except to go to a lighter spring when tuning the action.

 

Flat springs like in the 1873 rifle are much shorter lived.

 

good luck, GJ

 

 

G J., I suspect you may have more spring expertise than many here (surely more than me), so I have a related question for you:

 

Does storing a coil spring under full load fatigue the spring tension and/or change the spring response perceptably (either speed, power or longevity)?  Logic seems to say YES, but I don't understand why that sustained tension should change a spring's heat treatment and/or molecular structure.

 

I actually tried it with one of my NMVs to see if it would lighten the stock (22#)  mainspring. I stored the pistol on full cock for about three months.  The hammer still broke primers just fine and it developed  no slack in its stroke.  But it did seem more sluggish -- slower in starting its stroke -- less crisp, and I was then able to outrun the lock when I slip-hammered the gun.   Can you share anything about related spring physics or metalurgy?

 

[Badlands Bob #61228]

The modern spring can take being compressed for many years and still function just fine.  The magazine springs in our issued Glocks stayed fully compressed for at least 10 years.  Never any signs of spring fatigue or loss of compression.  The department replaced the firearms every 10 years because the night sites would go dim.  I've never replaced a revolver spring because it lost it's temper.  It's just not a routine maintenance kind of thing.

[Garrison Joe, SASS #60708]

Most gun springs are not at full travel by design (compressed to coil contact, or stretched to just short of deformation) because of the weakening that can occur at those loads.  

 

A pistol magazine spring is about as heavily loaded as a light coil spring can be - the coils come close to being collapsed with mag fully loaded, and there are sharp turns in many places instead of a round, no-sharp-turns true cylinder coil design.  The common sense, field practice is to NOT leave a pistol magazine fully loaded for more than a month, then let it "relax" for a while.  Never seen a scientific study, but I'd be pretty sure that some of the gun companies conducted some back when they started designing guns with coil springs rather than flat springs.  And I've got several magazines that their manufacturers recommend not storing loaded except for the few magazines kept for personal defense, and then replacing those springs after a couple of years of "standing by."

 

I also know from field experience that large coil springs in truck suspensions can be heavily loaded for a long time, but SOMETIMES will either weaken (sag) or fail (break apart) over 10 to 20 years of heavy use.

 

I wish my metallurgy training was more in the practical design of metal forming and welding, but mine was in the milling and extraction of metals from ores.  Yeah, I've been a copper and lead smelter rat, for first 15 years of my careers.

 

So, all that says to me - don't store springs at full load if you can avoid it.  If you can't, then learn what the "action" that the spring should provide feels like when new, and change springs when they no longer feel like that.  If a hammer no longer seems to have as brisk a fall as it used to, or won't do the job it has to do (fire a primer), then change the spring.

 

good luck, GJ

[Dusty Devil Dale]

1 hour ago, Garrison Joe, SASS #60708 said:

Most gun springs are not at full travel by design (compressed to coil contact, or stretched to just short of deformation) because of the weakening that can occur at those loads.  

 

A pistol magazine spring is about as heavily loaded as a light coil spring can be - the coils come close to being collapsed with mag fully loaded, and there are sharp turns in many places instead of a round, no-sharp-turns true cylinder coil design.  The common sense, field practice is to NOT leave a pistol magazine fully loaded for more than a month, then let it "relax" for a while.  Never seen a scientific study, but I'd be pretty sure that some of the gun companies conducted some back when they started designing guns with coil springs rather than flat springs.  And I've got several magazines that their manufacturers recommend not storing loaded except for the few magazines kept for personal defense, and then replacing those springs after a couple of years of "standing by."

 

I also know from field experience that large coil springs in truck suspensions can be heavily loaded for a long time, but SOMETIMES will either weaken (sag) or fail (break apart) over 10 to 20 years of heavy use.

 

I wish my metallurgy training was more in the practical design of metal forming and welding, but mine was in the milling and extraction of metals from ores.  Yeah, I've been a copper and lead smelter rat, for first 15 years of my careers.

 

So, all that says to me - don't store springs at full load if you can avoid it.  If you can't, then learn what the "action" that the spring should provide feels like when new, and change springs when they no longer feel like that.  If a hammer no longer seems to have as brisk a fall as it used to, or won't do the job it has to do (fire a primer), then change the spring.

 

good luck, GJ

Thank you!  I guess I never thought about coil springs having irregularities  (weaker points),  and not being a uniform cylinder.  That's an interesting line of thought.

 

Neither have I found actual results of  studies.  The closest I've come is Bill Bryson's book, "Heat Treating, Selection, and Application of Tool Steels".   He goes into crystal formation during heat treatment for varied deformation resistance and breakage/failure prevention, but not into spring fatigue or longevity.  The gun and other tooling industries must have done testing, but if so, it does not appear to be published or available.  If anybody finds or is aware of any actual comparison studies, I would appreciate a reference or link.

Thank you again. DDD

[Cheyenne Ranger, 48747L]

found a good cleaning often solves light hits

 

bought my Vaqueros in 2003--changed to lighter springs--still running same ones

[Marauder SASS #13056]

First, always change springs on a Thursday.

 

Springs wear mostly from being flexed - not compressed or extended.

So after many thousand "rounds" of firing and dry fire will eventually lighten the spring.

[Griff]

On 5/10/2023 at 7:24 PM, Johnny Swan, SASS #50322 said:

How many rounds do you run on 15 lb Wolff springs before you change them. Springs are on NMV

When they break or lose tension.  I like when the second occurs... but the 1st occurrence is the usual scenario.  In 38 years of cowboy shooting, I've broken two mainsprings, one in a Colt SAA after being trimmed by Bob Munden... some 8 years later.  My homemade replacement has been in that gun since 1994.  The other was a factory Uberti mainspring in my 1986 mfg'd 1873 Sporting Rifle in about 2018 or 2019.  I just replaced it with another factory one.  I don't believe that one can ever know just when a spring will fail.  And, said occurrences are fewer and farther between that most believe.  

[Marauder SASS #13056]

Springs normally fail on Fridays.  That's why you change them on a Thursday.  I'm surprised Griff didn't mention that! 

[Dubious Don #56333]

On 5/10/2023 at 9:10 PM, Garrison Joe, SASS #60708 said:

I run 1911s with many more rounds than any of my revolvers, and I change the mainspring (hammer is driven by the mainspring in that gun) at about 50 thousand rounds.   Good coil springs last for many many cycles.

 

Have never changed a revolver spring except to go to a lighter spring when tuning the action.

 

Flat springs like in the 1873 rifle are much shorter lived.

 

good luck, GJ

 

 

 

 

How about 1911 recoil springs? My carry guns generally, about every 3000-5000. For my Sig Scorpion, that was about two years, bought the gun my initial run before carrying was just shy of 2000, couple years of quals and shooting practice, week at Gunsite, the following year (@5000) I noted the recoil spring was a bit shorter than a new one and less "spring" of course, typical longevity in my experience for 1911 recoil springs. Never had a malfunction I didn't induce myself.

[Marauder SASS #13056]

I think it is normal for a used spring to be shorter.  That can happen pretty quickly but the spring lasts a long time after that.
I've heard that you test the recoil spring by holding the slide while slowly letting it move forward.  If it closes the action, the spring is still good. 

 

If it doesn't fully lock in battery, time to change it, especially if it's Thursday!

[Garrison Joe, SASS #60708]

I change a 1911 recoil spring after about 5,000 rounds.  That's a heavy shooting schedule year for me.   I find the recoil spring changes much faster (has shorter life) than the mainspring.  It's thinner wire, larger outer diameter, and spaced widely between turns.  For Wild Bunch PF (about 165) in a broken in 1911 - I run a 15# recoil and 19# main.

 

good luck, GJ

[WOLFY]

change them if they fail to ignite your hardest primers

 

(practice with that ammo)

[Marauder SASS #13056]

14 hours ago, Garrison Joe, SASS #60708 said:

I change a 1911 recoil spring after about 5,000 rounds.  That's a heavy shooting schedule year for me.   I find the recoil spring changes much faster (has shorter life) than the mainspring.  It's thinner wire, larger outer diameter, and spaced widely between turns.  For Wild Bunch PF (about 165) in a broken in 1911 - I run a 15# recoil and 19# main.

 

good luck, GJ

When you think about it, the recoil spring does a LOT of work.  Usually, more than the hammer spring.