22 Revolver Needs Help

[rck281]

I have a J-frame Model 34-1 revolver that dates to the mid 1970's. I am having a problem with failures to fire on approximately 1 cartridge out of every 6. Of course, this is worse in double action. I have done the following:
* Tried different brands of ammo but primarily use CCI
* Replaced the mainspring with a new one from S&W
* Replaced the firing pin with a slightly longer on that was machined by a friend.
* Added a small spacer under the mainspring to increase force.
* Contacted Wolff to inquire about an extra strength spring. They do not have such an item.
* I sent the gun to S&W but they won't work on it. They said it was "ghost material" due to it's age.

Any suggestions of where I go from here. Thank you.

 

[Seven High]

I suggest that you detail strip all the internals, thoroughly clean it, then lubricate the internals.

 

[arjay]

Are any of the chambers tight?.I wonder if one or more rounds isn't seating properly

 

[ArchAngelCD]

You said 1 out of every six rounds. Do you know if the misfired rounds are in the same cylinder hole? I'm not sure if it matters but any additional information is going to help.

I agree a good detailed cleaning and lube with a light gun oil can't hurt either. (Rem oil is still good)

 

[OutWest50]

You might possibly check to see if you have any cylinder endshake as well as the headspace distance.

 

[rck281]

You said 1 out of every six rounds. Do you know if the misfired rounds are in the same cylinder hole? I'm not sure if it matters but any additional information is going to help.

I agree a good detailed cleaning and lube with a light gun oil can't hurt either. (Rem oil is still good)

The problem doesn't seem to be isolated to a single charge hole. The internal has been cleaned and lubricated.
Sorry, nothing that easy. It seemed tight to me but I haven't really tried to measure for end shake.

 

[Heinz]

Have you tried reinserting the unfired round or turning it slightly. Modern 22 lr quality standards seem to have gone way down.

Will the unfired rounds go off in another gun?

 

[RGPM1A]

If you look at the Wolf spring website under J Frames they show the factory mainspring is 8.5lb. and that they have a 9lb. extra power spring (part number 23809). Since you changed out the mainspring already with a stock S&W spring I would try the Wolf 9lb. unit.

Alternatively I would try stretching the old spring out a bit (about 1/8" to 3/16") and give that a try.

My 2 cents

 

[Jimmyjones]

When my 34 gets dirty I get misfires, they all go off after a second hit. I found that they weren't seating fully. The first strike seats them and the second strike sets them off. I now keep a bore brush in my range bag and clean the cylinder every few cylinders. It also helps with the extraction. Mine has some sticky chambers and really needs to have a reamer run through it.

 

[armorer951]

Another viable possibility is shooting or cleaning debris under or on the extractor.

 

[max503]

I would look into reaming the cylinders. I did it to mine and it has made all the difference.

 

[pistolpete10]

I had a 36 that once in a while the hammer would hit the hammer block and misfire(don't ask me why it wasn't pulled down far enough) I don't know.

 

[MygunisaS&Wrevolver]

I had a 36 that once in a while the hammer would hit the hammer block and misfire(don't ask me why it wasn't pulled down far enough) I don't know.

I had the same issue with my model 63, I stoned a slight amount off of the top of the hammer block and it then fired fine. I made sure that the hammer block was still fully functional.

Before I discovered this, I also went with new springs, cleaning under the ratchet, removing the firing pin and replacing it. I was about ready to use my model 63 as a very expensive sturgeon sinker.

I would Dychem the top of the hammer block and see if it is hitting. This will tell you for sure. Mine would hit the top of the hammer block and then slide down causing light strikes and misfires. It only would do it about every three shots.

 

[rck281]

Thanks for all the help. I'll order the Wolff spring tomorrow.
I'll also check the hammer block (I never thought of that.)

Yes, the 22's do fire when hit a second time. I thought about the seating issue and made sure I pushed them all the way in, unless they are bouncing back out under recoil.

 

[retired2006]

Be aware that rimfire "J" frame mainsprings have a higher spring rating than the centerfire springs. The factory rimfire springs are red in color.

 

[rck281]

Update:
First - the spring I received from S&W was NOT red in color. Correct spring?
I purchased the 9lb spring from Wolff and shot it today. I also removed the hammer block to eliminate that possibility from this test firing.
It is improved but not fixed. With CCI ammo it seems to reliably fire in Single Action. About 1 in every 6 rounds doesn't fire in DA shooting. The indentions look the same to the naked eye. The rounds fire when hit in the same spot a second time.
I only had 14 rounds of Aguila but the all fired when shooting DA.

I'm going to try and find some other brands of ammo. It kills me to pay $10 for 50 rounds.
I also have a small spacer that I could place under the spring for even more tension. I just don't like degrading the trigger pull even more.
Will continue to report and appreciate suggestions.

 

[armorer951]

Can you check the headspace with a feeler gauge? (space between the rear of the cylinder and the breechface, ck after a good cleaning and wipe down)

It should be .008"- .010". Smaller is better.

 

[Mike SC Hunter]

You might possibly check to see if you have any cylinder endshake as well as the headspace distance.

Which can easily cured with a yoke washer.

 

[stu1ritter]

When you replaced the firing pin did you clean out the well that the firing pin sits in? Doesn't take much crud to hold the firing pin back slightly when hit by the hammer in a situation where thousandth's really count.

Stu

 

[robertrwalsh]

My guess (for what that might be worth to you) is either crud in the firing pin hole or the rounds are not seating 100% solid. Try after loading go back around and PUSH DOWN HARD on each round before closing the cylinder. It takes a hard, solid hit to set off rim fire ammo, harder than for center fire ammo.