Primers

[VNK971]

I've been having light strikes with a Model 10 and Model 15. I put in a new main spring and cleaned and oiled the works in both. Shooting reloads with CCI 500 primers still getting light strikes with the 10, but not as many; and none with the 15. New-to-me K-38 and M&P Target. Same reloads, no light strikes with K-38, some with M&P. I shot some remanufactored LSWC in the 10 with no light strikes. Anybody have luck with other primers?

 

[OKFC05]

Federal is the usual choice of revolver competitors. Care must be taken to ensure that the primer is fully seated because with a high primer often the first strike merely seats the primer and it takes a second to fire it.


Have you checked that your mainspring strain screws are standard length and fully seated?

 

[DWalt]

If you have put in new hammer springs and tightened the spring tension screws all the way, you should not be having any failures to fire with any brand of primers. You could have short tensioning screws so you might try putting fired primer cups under the tips of those screws.

 

[VNK971]

Yes, after cleaning, and new main springs, the strain screws were checked. Now I'm going to try different primers.

Edit: I had light strikes the first time I shot the 10 with factory ammo. The main spring in the 15 was not for a K frame. I could tell which cases came from the 10 because the dents were always smaller and not as deep.

 

[Rule3]

Yes, after cleaning, and new main springs, the strain screws were checked. Now I'm going to try different primers.

Edit: I had light strikes the first time I shot the 10 with factory ammo. The main spring in the 15 was not for a K frame. I could tell which cases came from the 10 because the dents were always smaller and not as deep.

The main spring (hammer) spring is the same for K L N frame guns.

So you have something else going on, I doubt it seriously it is the primers, Perhaps check you firing pin,99.9% of the time the primers are not seated correctly.

 

[4barrel]

If you think you have a primer problem punch it out and hit it with a hammer on a hard surface. I did that to my cap gun when I was 7 or 8 with a whole roll. My ears still ring.

 

[SMSgt]

Primer brand does not cause light strikes. That is either a primer seating problem, over quoted IMO, or a firearm problem. A firearm with a solid, reliable firing pin will fire even high primers.

 

[radio11]

I'm thinking firing pin.


Sent from my iPhone using Tapatalk

 

[S&WIowegan]

So that we can all stop guessing; What kind of firing pins do you have? Are they old-fashioned hammer mounted or the newer frame mounted. Your answer makes a big difference. Hammer mounted FPs rarely cause light strikes. Frame mounted FPs do sometimes have problems. It is possible for either type of FP to be broken.

My money is on poorly seated primers. Some reloaders are reluctant to seat them deep enough.

 

[scooter123]

So that we can all stop guessing; What kind of firing pins do you have? Are they old-fashioned hammer mounted or the newer frame mounted. Your answer makes a big difference. Hammer mounted FPs rarely cause light strikes. Frame mounted FPs do sometimes have problems. It is possible for either type of FP to be broken.

My money is on poorly seated primers. Some reloaders are reluctant to seat them deep enough.

A year of so ago I picked up a 19-3 at a gun show that was nearly unfired based on the lack of ANY marks on the recoil shield. First time at the range I found out why, the hammer nose was so short that it only projected through the firing pin bushing by about 0.03 inch. Quite simply it failed the "Dime Test" by a wide margin. Tried using an empty Large Pistol Primer cup to increase the DA trigger to over 11 lbs. and that provided only a tiny improvement.

The solution was to purchase a Power Custom Hammer Nose from Brownells. BTW, Brownells listed this kit for 19-4 and later but it was a drop in matter in my 1972 vintage 19-3. I will also say that the instructions for fitting provided were EXCELLENT and very descriptive of the "fitting points". So if you do need to do a bit of fitting it's not at all difficult. In my case the only thing I had to do was use a diamond file to shorten and round the tip by about 0.015 inch. Because these hammer noses are provided as an "Extra Length" part and they weren't kidding, the dimples from the first test were deeper than any firing pin strike I have ever seen. After that bit of adjustment they are still rather deep but not so deep to cause me concern about piercing a primer.

Finally, based on the appearance of my 19-3 it quite likely shipped from the factory with that short hammer nose. So that bit about the P&R revolvers being 100% perfect is IMO a myth. On the plus side now that it functions properly I've returned the mainspring tension to it's original state with a 9.0 lbs. DA trigger per my Lyman Digital Trigger Gage. I can also state that if you take care with sight alignment the 2 1/2 inch 19-3 is accurate enough to consistently hit a 12 inch gong at 50 yards. Yeah, I do cheat and shoot in single action when I'm testing myself that far out.

 

[Rule3]

The "odds" of light primer strikes on two different guns is pretty remote.

It was not mentioned if they where double struck or fired again?

Re manufactured ammo worked, so that kinda indicates its the primer seating.

Any easy test is buy a box of regular factory ammo and use them, If they work than you have your answer

 

[scattershot]

You didn't say if you were getting the light strikes with single action or double action. A too light hammer spring will give you misfires on DA, not so much on SA.
My immediate reaction would be that the new hammer spring is too light.

 

[Peak53]

...or the rebound springs have been shortened. Check for 17 coils and/or replace with OEM. Did these two guns come from the same source?

 

[VNK971]

Thank you all for your replies. The main spring in the 15 was not correct an replacing it fixed the problem with that revolver. After reading all the input, I'm going to try the Power Custom Hammer Nose for the 10 to see if that corrects the problem. I'll post the results, good or bad.

 

[Rule3]

...or the rebound springs have been shortened. Check for 17 coils and/or replace with OEM. Did these two guns come from the same source?

The rebound spring has nothing to do with striking the hammer striking the firing pin/primer??

 

[Deadctr]

I'd side on the primers not being seated properly.

Sometimes on my progressive I find that I've not made a full stroke to the "stop", ending with slightly high primers. 99% of my "light strikes" fire when struck again.

 

[JohnK]

I solved my "sometimes" light primer strikes, by using an RCBS hand priming tool.

You can "feel" the primer seating fully, to the bottom of the primer cup.

All my K frame .38/.357 guns have had action work, for a lighter trigger pull. Most have reduced power Wolff springs installed.

Works for me.

 

[daniel lawecki]

Are you seating your primers with a reloading press or hand held such as a Lee ? Seat the primers deeper with your press or hand held. When seating primers getting the right feel is important part.

 

[ArchAngelCD]

Thank you all for your replies. The main spring in the 15 was not correct an replacing it fixed the problem with that revolver. After reading all the input, I'm going to try the Power Custom Hammer Nose for the 10 to see if that corrects the problem. I'll post the results, good or bad.

Did you get both revolvers from the same seller? If yes, considering the spring was incorrect on the M15 it's also possible the strain screws were "modified". Before spending money on a custom hammer nose I would order a factory strain screw (or two) from S&W.

 

[rwsmith]

Neither of those guns........

Neither of those guns should have any trouble at all firing any primer that is made. The CCIs ARE hard, but again, there is nothing weak about a K frame Smith and you should only have a misfire rarely due to a bad primer. Something has been altered in those guns. I used to shoot CCIs in my mod 10 all the time and had primers fail, but with a nice, big hammer nose shaped dent in the middle of it.