Misfire Question

[.357MagNYC]

I took my 586-4 to the range today, and had 4 misfires out of a total of 50 rounds using factory FMJ 38+p ammo (unfortunately I forgot which brand).

After one misfire, I fired the next few rounds, then emptied the cylinder, put the unfired round back in, and it fired on the second try. But the other 3 would not fire in the 586 even after a few tries. (All the other 46 rounds fired as the should, no problem.) So I borrowed a Model 10 from the range. Two of the "dud" rounds fired on the first try, but the third one misfired on the first try before firing on the second.

I checked the strain screw on the 586 and it's tight. Do you guys think this is an ammo problem or a gun problem? I've occasionally had a round misfire here and there with my revolvers before, but it's only been 1-2 a box, and I've always just chalked it up to poor quality control on the ammo.

Thanks!

 

[Dragon88]

Sounds more like an ammunition issue, since the rounds misfired in two different guns. You don't remember the brand? There's a big difference between Federal/Winchester/etc factory ammo and Bubba's Gunshow Special "Factory" ammo.

 

[.357MagNYC]

My wife just told me it was Speer Lawman. That's what they usually have at the range, but I've never had so many misfires before. I'm hoping it was just a bad batch.

 

[gboling]

Between my son and I we have 10 S&W revolvers. The only one to have had a problem with misfires was a used 686 he bought. In that case the hammer spring was weak, supposedly from an attempt to reduce the trigger pull. A new spring solved the problem. The old hammer spring was notably straighter and weaker than the new one.

Was your ammunition new? I cannot believe that any recent amunition from Speer would misfire in a reliable S&W. I would take a serious look at the gun as you indicate that this problem is not new.

I have seen shortened strain screws and bent hammer springs cause this.

 

[Titegroups]

There must be a bit more to this story.

 

[H Richard]

What are the primer indents like? Are they just a shallow dimple? Do you have a friend who has a 585-686 which you could measure the firing pin protrusion and compare to yours? This is beginning to sound like a short or damaged firing pin. My 686-0 pin measures .200" from the hammer face to the pin tip.

 

[.357MagNYC]

I wish I would've saved some of the shell casings to post pictures of the primer indents. I remember what they looked like, but I can't say for sure if they were shallow, as I haven't really paid attention to the indents before and so can't compare.

The hammer spring doesn't appear to have been tampered with, so I'm guessing if it is the gun, then it must be the firing pin. I had a friend at the range take a look at it yesterday, and he said it looked ok, but I will try to post a picture when I get home later.

And just to be clear, my 586 has been pretty near 100% reliable up until yesterday. When I said I've had a round misfire before, I should've specified that it's probably been less than 5 times total on either my 586 or my 19-5 out of 1,000 rounds, and the round has always fired on the second try. Yesterday was the first time that I just couldn't get those rounds to fire from the 586.

Thanks for all your help, guys. Do I need a special tool to measure the firing pin?

 

[BSA]

Pard,

Personally I find your failure to fire rate of 5 out of 1,000 rounds unacceptable. I expect my guns and ammunition to go bang the first time and every time I pull the trigger. If they don't I have them repaired. I live with a little heavier trigger pull just to ensure the primer will go pop regardless of the brand.

I apply this standard to my self-defense, target and plinking firearms and I do reload most of my ammunition. The only time I will accept misfires is when I am shooting up old ammo that has been stored improperly or I do not know it's history.

Since you said you have had misfires in your Model 19 I would guess your problem is not the ammunition assuming it is factory fresh stuff.

 

[.357MagNYC]

^Not sure what you're trying to say there, BSA. So the fact that I've had a few failures with my 586, my 19, and one with the range's Model 10 makes you think the problem is not the ammunition? Are all the guns defective?

Anyway, here are the pics of my firing pin and hammer spring. Please let me know if you guys think anything looks amiss (aside from my shoddy photography--sorry).

 

[Nightowl]

I would expect Lawman to use CCI primers, which is noted as probably the hardest to ignite of all USA primers. Add in some endshake and maybe a short mainspring scres and you could get some light hits. As you had trouble in three guns I would suspect bad ammunition. However, the mainspring looks like it should have more bend in it than it does, so a change in strain screws may be a place to start.

 

[Fishslayer]

Generally a round that goes "click" the first time & "BANG" the second time is a primer not fully seated. The first strike seats it & the second one ignites it.

If they were handloads that would be my first guess. Dunno about Speer factory stuff.

 

[BSA]

357magNYC,

If you were shooting factory fresh Speer Lawman ammunition then I lean towards the problem being with the gun. Commercial ammunition is made to such high standards that even one misfire is rare, let alone 5.

On the other hand if you were shooting somebodys brand X reloads then I would suspect the primers are not being seated deep enough. As Fishslayer says the first strike seats the primer, the second strike fire it.

The only real way to check this is to buy a different brand of commercial ammo and fire it in your gun.

If you purchased your guns used then strong consideration so be given about them being the problem. In other words the previous owner traded his problem gun off onto someone else (unfortunately you). It is very difficult to describe everything you should look for when buying a revolver without shooting it.

My first suggestion is to buy another brand of commerical ammunition and test them as this is the cheapest fix. If you still have even one misfire I would take the gun to a good pistolsmith. Probably the surest and easiest way to get it fixed would be to send it to Smith & Wesson for repair.

You should not tolerate any misfires in your gun assuming good quality ammo. I have revolvers that have had many thousands of rounds fired through them without a single problem. (Well except for the nut behind the trigger).

I hope this helps.

 

[gboling]

^Not sure what you're trying to say there, BSA. So the fact that I've had a few failures with my 586, my 19, and one with the range's Model 10 makes you think the problem is not the ammunition? Are all the guns defective?

Anyway, here are the pics of my firing pin and hammer spring. Please let me know if you guys think anything looks amiss (aside from my shoddy photography--sorry).

Considering the law of average, I would suspect all three guns before I would suspect new Speer Lawman ammo.

The firing pin looks good. The strain screw looks good but it may not be completely seated as it appears that too much of the screw head is exposed. It is impossible to tell the condition of the hammer spring by looking at it while it is in the gun.

A test of the hammer spring would be to measure the weight of the triggger pull in double action. Another test would be to take it out and check it's curvature beside a new one.

 

[BSA]

Help me out pards.

As I studied the pictures 357magNYC posted I realized his 586 did not have the lock and was round butt. Did all of the 586's without the lock come with a square butt? If so then this gun has been worked on with someone with a grinder and file.

Looking the mainspring over I am inclined to agree with gboling about the mainspring not having enough curve and as a result not having enough strength.

I have done round butt mods to some of my guns and I found the most critical part is getting the depth of the hole for the strain screw and getting the length of the strain screw correct. I would trace the outline of the grip and of the curve of the mainspring on a piece of paper and match my work to it. I never had any problems with misfires with this method.

357magNYC can you tell by looking at the back of the backstrap and lower part or the front strap if it has been ground off? If it has been cold blued then it probably has.

 

[47D]

Did all of the 586's without the lock come with a square butt?

No. They were made in both round and square. In 1995-96 the square butt was deleted, leaving only the round butt.

 

[.357MagNYC]

357magNYC,

My first suggestion is to buy another brand of commerical ammunition and test them as this is the cheapest fix. If you still have even one misfire I would take the gun to a good pistolsmith. Probably the surest and easiest way to get it fixed would be to send it to Smith & Wesson for repair.

Thanks, BSA, and thanks again to all of you for the info and advice. The next time I go to the range (unfortunately it won't be until the weekend after Thanksgiving), I'll shoot another brand of ammo, and maybe some Speer Lawman again as well. If I have issues with misfires again, then I'm sending it to the smith.

M 586 had been great up until Sunday, so I'm not quite ready to call it a "problem gun" yet. (And from the looks of things I doubt it's been worked on much by the previous owner.)

Are replacing the strain screw and/or hammer spring considered routine maintenance? Is it something I should do on my revolvers after a certain number of rounds?

 

[BSA]

Are replacing the strain screw and/or hammer spring considered routine maintenance? Is it something I should do on my revolvers after a certain number of rounds?

No it is not. A common practice of shadetree so-called gunsmiths is the shorten the strain screw and thin and rebend the mainspring in order to get a lighter trigger pull. A old timers trick was to place a piece of leather between the strain screw and mainspring to lighten the trigger pull. The trade-off is getting to light of of tension on the spring and experiencing misfires such as you are having.

Another common cause of misfires is excessive headspace on the cylinder which has already being mentioned. This is something that should checked by a gunsmith.

Keep us posted on your results.

 

[.357MagNYC]

Went to the range today and had more misfires, so I'm having the gun checked out. I used Speer Lawman again, and there was one misfire every 6 rounds. They were all coming from one chamber, too--is that just a coincidence?

The unfired primers had a very tiny dimple on them, while the fired ones had a much bigger dent. All the misfired rounds later fired no problem through the range's 686. I'll keep you posted once I hear back from the experts. Thanks again everyone for your help.

 

[shawn mccarver]

Went to the range today and had more misfires, so I'm having the gun checked out. I used Speer Lawman again, and there was one misfire every 6 rounds. They were all coming from one chamber, too--is that just a coincidence?

The unfired primers had a very tiny dimple on them, while the fired ones had a much bigger dent. All the misfired rounds later fired no problem through the range's 686. I'll keep you posted once I hear back from the experts. Thanks again everyone for your help.

Send that gun back to S&W and have them fix it. Likely, it has had an attempted "trigger job" that has made firing pin indents too light.

 

[dirty gary]

Sounds like a gun issue - however, don't think that "factory" ammo is immune to mistakes. I worked at a reloading company for years, and we found many rounds with mistakes in factory loadings - for instance, a 9mm Federal Hydra Shok with an upside down primer, a Winchester Silver Tip 40 with the bullet loaded upside down, and my favorite, a Remington Golden Sabre 45 with no extraction groove formed at the base. Always check your ammo - Remember, the best safety is between your ears