.357 Misfires

[GypsmJim]

I can't remember the last time I had one.

Today had 2 revolvers out on the range and in 25 rounds had 6 misfires with a model 19-4. Two of them fired the second time. The other 4 fired when I put them in another gun (a Ruger).

Switched to .38 spl and had 1 misfire in 50 rounds.

I am using the same component brands as i have for the last 35 years. The 38's were newly made and the .357's were several year old.

All of the primers had normal strikes. The Ruger did make a sllightly bigger dent, but the Smith still looked to be OK. The misfires were visually not light strikes.

The firing pin looks OK and the gun does not seem to be dirty. Let me emphasize that I have been firing this gun for months without a hiccup.

Where should I look next?

 

[ronnie gore]

MISFIRE

i have been getting some misfires with new winchester primers copper colored, never had them before.

 

[GypsmJim]

These were CCI primers.

 

[Neal]

I can't remember the last time I had one.

Today had 2 revolvers out on the range and in 25 rounds had 6 misfires with a model 19-4. Two of them fired the second time. The other 4 fired when I put them in another gun (a Ruger).

Switched to .38 spl and had 1 misfire in 50 rounds.

I am using the same component brands as i have for the last 35 years. The 38's were newly made and the .357's were several year old.

All of the primers had normal strikes. The Ruger did make a sllightly bigger dent, but the Smith still looked to be OK. The misfires were visually not light strikes.

The firing pin looks OK and the gun does not seem to be dirty. Let me emphasize that I have been firing this gun for months without a hiccup.

Where should I look next?

How is the head space? Do you have any end-shake in the cylinder? Is your strain screw all the way in? Did you check the ammo for high primers? Just tossing out some things to check that could cause problems lighting ammo.

 

[bountyhunter]

Considering the widespread shortages of ammo and primers, it would not surprise me if QA had gone away.

 

[handgunner356]

I have yet to have a "bad" primer. It has always come down to the usual suspects, high primer, loose strain screw, weak mainspring or worn/broken firing pin.

 

[GypsmJim]

The headspace is 0.017" and the cylinder gap is 0.003". End shake is hardly detectable and I couldn't measure more than maybe 0.001".

The strain screw is all the way in. The firing pin "looks" OK, but not sure how to check that or the mainspring.

The primers are all seated flush.

The "worst" box of ammo was loaded several years ago and the "better" one last winter, so primer lots were several years apart.

I've owned the gun and have been shooting it for a year now with PMC brass that I bought last year as well. The only difference yesterday was that my "new" brass had not been reloaded, so I used a couple boxes of older Speer brass that I had for ages.

I

 

[scooter123]

One possibility is that "old" brass had deeper primer pockets. If so, the primers may not be fully seated in the casehead and that's an invitation for misfires. Another possibility is that your primers were exposed to some moisture in storage and this has resulted in primers that aren't quite as sensitive as they need to be in you model 19.

Another possibility that comes to mind is that your firing pin needs to be replaced. Note, this is assuming that your running your model 19 with the factory mainspring setup and the strain screw hasn't worked loose. With the hammer mounted firing pins, checking this is very simple. Open the cylinder, pull the cylinder release to the rear and drop the hammer fully forward. Now take a dime and lay it alongside the tip of the firing pin projecting through the recoil shield, if it's the correct length it should be even with the surface of the dime.

BTW, this test doesn't work with the frame mounted firing pins because they only project through the recoil shield by about half as much. Note, I'm still scratching my head how firing pins with a much shorter projection can prove reliable but I haven't had any problems with misfires on my newer guns with the frame mounted pins. I also tried an extended firing pin in my 610-3 and put the standard pin back in when I saw evidence of microscopic leakage in about 30% of the rounds fired with the extended pin.

Final possiblity is that the tip of the strain screw in your model 19 has mushroomed enough that it's reduced the power of your hammer strikes, or the mainspring needs to be reshaped. I've heard, but not tried it, that placing the mainspring on a table with the arch up and tapping it with a plastic hammer will "reset" the mainspring so that it will again function as new. It might be worth a try doing this, however I would trace the current arch on a piece of paper and do a bit of comparing while doing this. Take about 1/8 inch of the arch out at the midpoint and it may solve your problem.

 

[kewpie]

Misfires

These were CCI primers.

Very interesting.

Some months ago I bought a M 66-5 3.25" from a friend. I loaded about 100 158 LSWC's w/ 4.5 gr Unique and CCI SP primers that are at least 25 years old. I went to a local range and fired all 100 with no problem.

Last month, going to a CCW class, I figured I would load 100 LSWC with 'new' primers to 'ensure' that they all fired. I bought 100 brand new CCI small psitol primers @ Gander Mountain and loaded same bullet and powder charge.

I had 2 misfires with the 'New" primers. (Both did fire on second time around the cylinder FWIW - which is not much

 

[Neal]

Very interesting.

Some months ago I bought a M 66-5 3.25" from a friend. I loaded about 100 158 LSWC's w/ 4.5 gr Unique and CCI SP primers that are at least 25 years old. I went to a local range and fired all 100 with no problem.

Last month, going to a CCW class, I figured I would load 100 LSWC with 'new' primers to 'ensure' that they all fired. I bought 100 brand new CCI small psitol primers @ Gander Mountain and loaded same bullet and powder charge.

I had 2 misfires with the 'New" primers. (Both did fire on second time around the cylinder FWIW - which is not much

I hate to read this about CCI primers. I have 20,000 on order that should be in this month.

 

[Neal]

Speaking of primers, I like to seat mine about .005" below flush. I have not had a primer failure in years. I like Federal and W-W best, but I found a good deal on CCIs, so I ordered 20,000 of them in LP. Hope I don't regret it.

 

[kewpie]

I hate to read this about CCI primers. I have 20,000 on order that should be in this month.

Just a rare anomaly. Probably will never ever occur again

 

[GypsmJim]

The "dime" test on the firing pin showed good projection.

I've been loading for 35 years in what I consider good conditions. After loading tens of thousands of rounds I have never had a primer misfire before, so I don't suspect moisture or bad primers.

As I said before, the rounds all went bang with the Ruger, that's why I suspect the Smith. But, having said that, the primer strikes on the misfires did NOT show light strikes.

Based on all the comments so far, sounds to me like the mainspring may need work. The previous owner told me he had a "trigger job", but I have no knowledge of how that was done or whether the spring is original or not. The trigger is surely smooth as silk (best gun I own), and the tip of the strain screw looks fine.

 

[handgunner356]

For no more than it runs I would go with a new mainspring first off. If all the rounds fired fine in your Ruger than it pretty much puts the gun in question.

 

[camper]

I had an average of two light strikes per seven round cylinder in my 686+ today. When I say light, I mean very light. Its going back to the dealer and S&W tomorrow. The first two were PMC commercial loads, the others, my loads. Not random though as the same problem occurred this past Saturday.

 

[dpsix]

It has been my experience that CCI's require more effort to seat and require a full power mainspring to reliably detonate. With stock mainsprings, CCI have not been a problem. I do prefer Federal's though.

 

[Alk8944]

I can't remember the last time I had one.

Today had 2 revolvers out on the range and in 25 rounds had 6 misfires with a model 19-4. Two of them fired the second time. The other 4 fired when I put them in another gun (a Ruger).

Switched to .38 spl and had 1 misfire in 50 rounds.

I am using the same component brands as i have for the last 35 years. The 38's were newly made and the .357's were several year old.

All of the primers had normal strikes. The Ruger did make a sllightly bigger dent, but the Smith still looked to be OK. The misfires were visually not light strikes.

The firing pin looks OK and the gun does not seem to be dirty. Let me emphasize that I have been firing this gun for months without a hiccup.

Where should I look next?

Sounds like primer contamination if the firing pin impression didn't show a light strike. Have you changed anything about how you clean your cases?

Over 50 years and well over a million rounds loaded and fired I have had only a few mis-fires, about 1974, and they were all in one box of ammunition! This was back in the days when steel dies were the norm and lube had to be cleaned from cases after sizing. I had decided to use Coleman Fuel to wash the cases after sizing instead of Carbon Tetra-Chloride, Trichloroethane or Perchlorethane as I had been using. Apparently there is enough oil in Coleman Fuel to kill primers within a few days! To my recollection I had never had a mis-fire in a handload before or after that one incident.