Need advice on Mdl 28 spring tension

[HarryH]

For the last 52 years I have proudly owned a model 28 Highway Patrolman revolver. It was my first handgun, and very much one of my favorites. I took it to the range the other day and fired about 100 rounds through it. Many were my reloads, and a few were new factory Gold Dots, in both 38 special and 357 magnum.

I had 2 "light hits." OK one of them was one of my reloads, but the other was a new factory 38 special gold dot. I immediately tried both light hits a second time and they fired.

So now I have lost some confidence in this gun for a bedside gun.

In cleaning the gun afterwards, I checked the hammer spring, which is a leaf type spring with a tensioning screw at the front of the grip area down low. It appeared normal.

I released all of the tension on the spring, and then tightened the screw about a quarter turn. I then reattached the hammer spring. I haven't fired the gun since.

I need advice on what the tension should be on that spring. I'm pretty sure it had not been changed in about 30 years.

I would think it would be something like:

1. Back off the tensioning screw all the way.

2. Screw it in until it JUST makes contact with the spring.

3. Then tighten it X amount of turns after that.

Can anyone advise me how to adjust this tensioning screw so that I can regain confidence that there won't be any more light hits?

 

[OldSmiths357]

I would not lose confidence after two light primer strikes. With primers and ammunition today, I would say very common. I have seen this will all major manufacturers in many different calibers. The strain screw should be screwed all the way in against the spring. From two factory armorers, this is how it is meant to be. If the strain screw is backed out, not flush with the front strap, the grips will not go on.

 

[mh51]

The strain (tension) screw should be screwed in until it bottoms out. Its set that way at the factory to insure reliable ignition and that it doesn't back out after repeated firing. It's not intended to be adjusted to lighten the trigger pull.

 

[jcelect]

Main Spring Tension

The main spring is the flat spring which, after many years of use, will retain an "arched" contour! This will lighten the spring tension which effects the hammers force against the primer! A quick fix is to place the cup of a fired primer, after removing the anvil, over the main spring tension screw and turn the screw in all the way and tighten it. If you buy a spring kit you will receive a new main spring and probably a choice of 3 trigger return springs
jcelect

 

[Alk8944]

As MH51 said, the mainspring tension screw is not an adjustable feature. Spring tension is set at the factory by shortening the screw as/if necessary. The screw is supposed to be tightened until it bottoms out against the frame, period!

You asked, we told you. If the screw is not fully tightened it will work loose under vibration of firing the gun and eventually result in light strikes. There is no reliable source that will tell you anything different.

You asked, we told you. If the screw is not fully tightened it will work loose under vibration of firing the gun and eventually result in light strikes. There is no reliable source that will tell you anything different.

It is a myth that a properly heat-treated spring will lose tension over time. I own several, well over a dozen, S&Ws that are over 100 years old, have their original springs, and all still work perfectly well. The only time the trick of placing a primer cup over the mainspring strain screw makes any difference is in cases where someone has shortened the screw improperly.

 

[minconrevo]

I too have owned a few S&W revolvers, most having the flat spring. It is essential that the strain screw be FULLY bottomed out against the spring, with the screw head fully in contact with the frame. It's unusual for the spring to work loose when fully tensioned down. I have never had a S&W flat mainspring loose tension by itself. Many years back, I did have one fail by breaking in the middle, which I ascribed to a bad lot of metal. That failure was immediate and obvious.

The "no go bang" condition could be aged lubricant gumming the lockwork. Could also be something as simple as unburned powder under the extractor star.

 

[stansdds]

Tighten the strain screw until it is all the way in and tight, it's not an adjustment screw, it's there to make installation and removal of the main spring possible.

 

[HarryH]

Hi, Thank you all for your knowledge and caring. I now understand to tighten the tension screw ALL the way in. I will do so.

I did ask Smith-Wesson about it, and they "hinted" that I could send it in and have them check it out, but they did NOT say for sure that they would pay for the shipping both ways or for sure if they would cover it under warranty.

On the message that I sent them I told them it was 52 years old. In reading their online warranty it says firearms made after 1989 have the lifetime warranty.

Should I just tighten the screw and NOT send it back to Smith?

 

[Pine_Worker]

Don’t send it back!

 

[rct269]

If you're in search of a lighter double action trigger pull, the answer is "Spring Kit" ($20-$30)----and it's the only answer for us amateurs.

There's a bunch of them! I know about only one, and that's the one by Jerry Miculek. It's main claim to fame is you can install it such as to have any trigger pull you want---with the proviso you don't go below 7 lbs-----which is to invite FTF's.

The one piece of advice and counsel I can offer is to READ and FOLLOW HIS INSTRUCTIONS ---unless, of course you're like me who's been there and done that, and have no need for any instruction to replace a couple of springs in a S&W hand ejector.

Then again, NOTHING would move when I finished up the first time around. It was all better after the second time around. That was AFTER I followed his instructions.

Ralph Tremaine

 

[Fullmetaljacket]

Don't send it back to S&W. Do these things first: 1) Fully tighten the strain screw. 2) If you have reasonable tool skills remove the side plate with properly fitting screwdrivers and give the innards a thorough cleaning. There may be some 50 year old oil in there that has turned to varnish and is gumming things up. 3) If neither 1 nor 2 works buy a new mainspring, they are readily available and cheap. Try Wolff Gunsprings to start, I would get both the factory replacement weight and the reduced power type and try them out. I'm betting some combination of the above solves your issue. Let us know how it works out.

 

[ggibson511960]

Springs Losing Tension

It is a myth that a properly heat-treated spring will lose tension over time. I own several, well over a dozen, S&Ws that are over 100 years old, have their original springs, and all still work perfectly well. The only time the trick of placing a primer cup over the mainspring strain screw makes any difference is in cases where someone has shortened the screw improperly.

Well said. I see "experts" tout this myth incessantly. None of them have a clue what a stress-strain diagram looks like, nor would they understand if they saw one. Springs store and release energy by deflecting in the elastic region of the curve, well below yield. High cycle fatigue will weaken or break a spring but the cycles number in the millions at reasonable temperature. All properly designed springs essentially have infinite fatigue life. The rare exception to this simple rule of physics and engineering is a spring that is abraded against a channel, spring guide or frame, reducing its cross sectional thickness.

Belief in this myth supports an industry of spring replacement and tyro gunsmiths. Few know what a spring constant is nor understand preload.