34-1 light primer strikes

[Nonno]

I picked up a very nice 34-1 snubby from about 1960, very good condition except for the cylinder drag line. (which is odd, since other than that there is very little sign of use. Bluing is beautiful, bore, forcing cone and cylinder all look almost new, everything nice and tight). But, I'm getting light primer strikes. About one round in ten with various types of ammo doesn't go boom the first time around, and everything shows light dents, not the usual sharp one, in the casings. Figuring it might be clogged up with old dried grease, I opened it and cleaned it, that didn't help. (photo prior to cleaning). Firing pin moves freely, about the same spring resistance as my 17-2. Double action is smooth, around 11 to 12 pounds, single action pull is very short and light, 2 to 3 pound and only requires the tiniest of movement to shoot. See the photo to see how far back the trigger sits in single action. I wouldn't mind a slightly heavier trigger pull.

Any suggestions?

 

[ggibson511960]

Aftermarket grips. Might the grip screw foul the hammer spring? It shouldn't, but there's not much clearance in the grip frame.

 

[Nonno]

Herrett grips, I just checked, there is about 1/16" clearance between the screw and the spring.

Aftermarket grips. Might the grip screw foul the hammer spring? It shouldn't, but there's not much clearance in the grip frame.

 

[Pisgah]

Someone may have done a "trigger job" on it by trimming coils off the mainspring. Bad idea.

 

[RMFnLA]

Someone may have done a "trigger job" on it by trimming coils off the mainspring. Bad idea.

This.

Common since the J frames have a fairly stiff mainspring because they are so small.

Try a replacement OEM, especially since you say you’re ok with a heavier trigger pull.

 

[Retired W4]

Two thing I would note about the pictures, neither of which may concern your problem. One, you don't show the sliding hammer block safety. Probably not a big deal. Second, the trigger rebound slide just does not look right, especially at the top rear. I tried to find one in my parts drawers for comparison with no luck. I've had them break there before.

It may indicate someone has worked on it in the past. Good luck with it.

Also, there may be some crud in the floating firing pin.

I would post in the "Smithing" section.

 

[gmborkovic]

Nonno, start cheap. You may have a dirty frame around the firing pin.
A spray solvent and compressed air can clean out a lot of crud.
Give it a try first.

 

[Nonno]

Two thing I would note about the pictures, neither of which may concern your problem. One, you don't show the sliding hammer block safety. Probably not a big deal. Second, the trigger rebound slide just does not look right, especially at the top rear.

Because of all the old oil and grease, the hammer block safety had stuck to the sideplate. Cleaned it all up and put it back together. I've attached a couple photos from the innards after cleaning so you can get a better look at the rebound slide. (hammer cocked and not cocked)

Nonno, start cheap. You may have a dirty frame around the firing pin.
A spray solvent and compressed air can clean out a lot of crud.

I tried to get Hoppes down in there, it seems to move freely, but I wouldn't be surprised if the spring is gummed up. I have some Break Bree CLP and Break Free Powder Blast, I'll try spraying one of those and blowing it out tonight.

Thanks!

 

[Hondo44]

I picked up a very nice 34-1 snubby from about 1960, very good condition except for the cylinder drag line. (which is odd, since other than that there is very little sign of use. Bluing is beautiful, bore, forcing cone and cylinder all look almost new, everything nice and tight). But, I'm getting light primer strikes. About one round in ten with various types of ammo doesn't go boom the first time around, and everything shows light dents, not the usual sharp one.

Any suggestions?

Check the cylinder bolt for a rough top surface causing a heavy ring around the cylinder; that’s the common cause. The first thing I do on any revolver is polish the bolt top surface!

You can’t tell anything from the firing pin dent on the case head or on the primer. An unfired cartridge will never have a deep dent like a cartridge that actually fires no matter how strong the hammer spring is.

 

[gmborkovic]

Get a thin wooden dowel and slide it down the barrel and chamber.
And pull the trigger. What happened?

 

[Nonno]

Get a thin wooden dowel and slide it down the barrel and chamber.
And pull the trigger. What happened?

Nothing. The strike is only on the outer rim, so it misses the dowel. I used a bamboo chopstick and shaved it down to fit.
I tried the same dowel in my 17-2, firing pin hits it and knocks it forward about 1/4".

Check the cylinder bolt for a rough top surface causing a heavy ring around the cylinder; that’s the common cause. The first thing I do on any revolver is polish the bolt top surface!

That could explain the cylinder ring, but the bolt does fully retract and doesn't pop back out until the end of the cylinder rotation, as it starts aligning with the teardrop dent.

I could polish it, does maybe feel a trifle rough to my finger, but I'm wary about messing with anything that could change the locking of the cylinder. But I guess you only do a couple strokes with a very fine stone? Or some flitz and 0000 steel wool?

 

[Model19man]

I But, I'm getting light primer strikes.

Pretty sure a Model 34 is a rimfire - there should not be any primers involved.

 

[Nonno]

Pretty sure a Model 34 is a rimfire - there should not be any primers involved.

yup, 22 lr, right, I used the wrong term. Light strikes, failures to fire.

 

[pharmer]

I get duds regularly (maybe 1 in 100 or so) with many different .22's. Today's rimfire ammo seems a little less quality controlled. Joe

 

[Nonno]

I get duds regularly (maybe 1 in 100 or so) with many different .22's. Today's rimfire ammo seems a little less quality controlled. Joe

True, although I'm getting more like 1 in two to four hundred with my other .22's. I'm getting at least one in ten with this revolver, same lots of ammo that is performing fine in my others.

One exception: There was one brick I got last month that was downright bad- Wolf match target. I only shot 100, but spread across two S&W revolvers, two Colt revolvers, and a Beretta Olimpia rifle shooting both bolt action and semi auto (that rifle is "select fire", shoots single shot bolt or semi). Of the 100 rounds, between 20 and 25 were duds. Ammo is going back to Wolf, they'll send a refund on the 400 I didn't shoot.

 

[Mike SC Hunter]

Put a small washer on the main spring strut and re-install the MS. That should make the MS stronger and lessen your misfires.........If that works get a new MS.

 

[rwsmith]

Does the model 34....

...have a strain screw? If so it could be loose or shortened in a poor man's trigger job.

 

[Muley Gil]

Coil mainspring-see photos in posts #1 and #8.

I had a M34 that would misfire on double action quite often. I changed to a stronger mainspring-no luck.

I finally sold it.

 

[oink]

You need to clean it better. It still looks gummy. Use a liberal amount of GunScrub spray or similar. Spray in every crevice and direct it behind all parts. (Or take it completely apart to clean.) Then blow it out with air and lubricate with a reasonable amount of proper lubricant.

 

[Hondo44]

That could explain the cylinder ring, but the bolt does fully retract and doesn't pop back out until the end of the cylinder rotation, as it starts aligning with the teardrop dent.

I could polish it, does maybe feel a trifle rough to my finger, but I'm wary about messing with anything that could change the locking of the cylinder. But I guess you only do a couple strokes with a very fine stone? Or some flitz and 0000 steel wool?

The full ring around the cylinder is from poor handling: closing the cylinder with no attention paid to the position of the cylinder notches relative to the cylinder bolt. Then manually turning the cylinder while the bolt slides around it until it finds a notch to drop into, instead of cycling the action to lock the cylinder.

The bolt surface is best honed with magnification using a fine flat stone being careful to maintain the slight surface angle and not round the edges. Flitz on a cloth wrapped tightly around the flat stone for final polish.