J frame timing issues?

[Nephrology]

So I am not sure if what I am observing is normal or not. Gun in question is a 442-2 no lock with an Apex spring kit (but OEM firing pin).

I was dry firing my J frame today and noticed that occasionally the trigger pull felt "different." When I normally pull a J frame trigger, I notice two distinct "clicks" before the firing pin drops. I attribute this to the cylinder stop unlocking and locking again as the cylinder rotates to bring the next charge hole in line with the breech face/firing pin.

However, about 50% of the time, I noticed that I am not getting the second click. When this happens, I can tell that the cylinder is not quite yet fully locked up, and that it doesn't appear to fully lock until the firing pin drops. These two things seem to happen simultaneously; when looking at the cylinder with the trigger held almost all the way to the rear, I can see that the cylinder isn't quite fully aligned. When I depress the trigger all the way, the cylinder seems to rotate a millimeter or two and locks into place while the firing pin drops at the very same time.

The other 50% of the time, the cylinder rotates into place with a sharp click and I still have a good amount of weight/travel to go before the firing pin drops. I can usually induce this if I "stage" the trigger. This is how I am used to the gun shooting.

I am probably just over thinking this, but is this normal? Or is this something I should have looked at?

[mtnbkr]

So I am not sure if what I am observing is normal or not. Gun in question is a 442-2 no lock with an Apex spring kit (but OEM firing pin).

I was dry firing my J frame today and noticed that occasionally the trigger pull felt "different." When I normally pull a J frame trigger, I notice two distinct "clicks" before the firing pin drops. I attribute this to the cylinder stop unlocking and locking again as the cylinder rotates to bring the next charge hole in line with the breech face/firing pin.

However, about 50% of the time, I noticed that I am not getting the second click. When this happens, I can tell that the cylinder is not quite yet fully locked up, and that it doesn't appear to fully lock until the firing pin drops. These two things seem to happen simultaneously; when looking at the cylinder with the trigger held almost all the way to the rear, I can see that the cylinder isn't quite fully aligned. When I depress the trigger all the way, the cylinder seems to rotate a millimeter or two and locks into place while the firing pin drops at the very same time.

The other 50% of the time, the cylinder rotates into place with a sharp click and I still have a good amount of weight/travel to go before the firing pin drops. I can usually induce this if I "stage" the trigger. This is how I am used to the gun shooting.

I am probably just over thinking this, but is this normal? Or is this something I should have looked at?

Give your gun a good cleaning. Remove the sideplate, remove the cylinder and crane, degrease and clean everything well. I've seen this happen with old, dirty guns.

If that doesn't fix it, then this could be an issue with the hand, which is not a task for most folks.

Chris

[LSP972]

Not normal; you're not over-thinking it.

What you're seeing is known as DCU; Does Not Carry-up. Several possible causes, but most likely is a worn hand.

Here's how it works: the hand is attached directly to the trigger, and engages the ratchets on the cylinder's extractor star through the slot in the recoil shield- known as the "hand window". Proper lock-up (prior to hammer fall) is dependent upon the hand being wide enough at the tip to push the cylinder all the way around to the next cylinder stop slot on the cylinder's outer surface. Remember, we have two different types of movement here- linear and rotational- working in concert.

You correctly deduced those two clicks you're hearing as part of this function; the front part of the trigger cams the cylinder stop up and down (locking/unlocking). The cylinder stop needs to drop at the start of the trigger pull, so the cylinder is free to rotate while being pushed by the hand; and then it needs to pop up into the stop notches on the cylinder to hold the cylinder in place to prevent side-spit/bullet shaving. IOW, we have lots of stuff moving here, in three different axes, that all must work together to avoid any binding/etc. Hence the term "timing".

On a target revolver, where one is using the single action/hammer cocking, or staging the trigger cocking movement, to make precise shots, this DCU is a definite problem. Let us agree that a J frame, of ANY stripe, is a looonnnggg way from being a target-grade piece. In the first place, you only have trigger cocking as an option on your 442. In the second place, you're going to pulling that trigger fairly quickly… and here is where you can stop worrying.

Because, until the hand gets REALLY worn, centrifugal force from your quick-starting the cylinder rolling with a hard "DA pull" means it will continue around to the next stop notch on its own. You'll know when it is worn to the point of needing attention when the gun starts side-spitting… caused by the charge holes NOT being properly aligned with the barrel's forcing cone and the bullet is actually being shaved at one point when the enters the forcing cone off-center. If you're not seeing that now… don't worry about it.

Unfortunately, I have zero clue how the MIM parts wear together. On the old system, with all milled/forged parts, the hand ALWAYS wore faster than the ratchets. This is why a serious PPC shooter would find the ideal hand width for his action, then have that puppy Armolloyed so it would not wear out too fast. But keep in mind, we're talking about tens of thousands of rounds before this became an issue. Easily attainable; in 1988, I fired over 85,000 wadcutters alone through my bull gun.

I have two points to make here, one at the risk of pissing some folks off. We'll cover THAT one last.

First, as noted, unless you are experiencing side-spitting, "shaving lead", or any of the other formerly-common names for a worn lock-up… don't sweat it. Keep an eye out for lead/bullet jacket build-up on ONE side of the forcing cone (need a strong light to see this). When you start getting either, or both, of these, then it is time to visit the doctor. And be DAMN sure your mechanic knows what the hell he is doing. Tell him your piece probably has DCU. If he gives you the RCA Dog Look, go elsewhere. You're dealing with a Glock/870 parts-changer who fancies himself a gunsmith.

Now, the second point. The only reason you even noticed the DCU is because you're trying to do some precision shooting… yes? WHY? If you feel the need to be able to make a head shot across a parking lot (and that is a worthy goal), a J frame isn't your huckleberry. I have seen this time and again on this forum, and have managed to keep my lip zipped because there aren't any idiots here. But guys, take it from someone who has carried professionally for almost 40 years, and investigated plenty of shootings… YOU NEED MORE GUN THAN A J FRAME FOR GENERAL DEFENSIVE USE.

I understand there are those who simply cannot- or WILL not- carry a serious handgun. Fine; get one of the all-steel Pro models, so near and dear to DB's heart, with an external hammer to handle those long shots. Those ARE capable of serious long-range work, and will hold up probably longer than an AirWeight… in terms of parts interaction.

Okay, I'm done. Sorry for the rant…

.

[Nephrology]

First, as noted, unless you are experiencing side-spitting, "shaving lead", or any of the other formerly-common names for a worn lock-up… don't sweat it. Keep an eye out for lead/bullet jacket build-up on ONE side of the forcing cone (need a strong light to see this). When you start getting either, or both, of these, then it is time to visit the doctor. And be DAMN sure your mechanic knows what the hell he is doing. Tell him your piece probably has DCU. If he gives you the RCA Dog Look, go elsewhere. You're dealing with a Glock/870 parts-changer who fancies himself a gunsmith.

Now, the second point. The only reason you even noticed the DCU is because you're trying to do some precision shooting… yes? WHY? If you feel the need to be able to make a head shot across a parking lot (and that is a worthy goal), a J frame isn't your huckleberry. I have seen this time and again on this forum, and have managed to keep my lip zipped because there aren't any idiots here. But guys, take it from someone who has carried professionally for almost 40 years, and investigated plenty of shootings… YOU NEED MORE GUN THAN A J FRAME FOR GENERAL DEFENSIVE USE.

I understand there are those who simply cannot- or WILL not- carry a serious handgun. Fine; get one of the all-steel Pro models, so near and dear to DB's heart, with an external hammer to handle those long shots. Those ARE capable of serious long-range work, and will hold up probably longer than an AirWeight… in terms of parts interaction.

Okay, I'm done. Sorry for the rant…

.

Thanks for the input. I appreciate. A few points/follow up questions :

1. The gun only has a little over 700 rounds through it so far, with maybe 5-10x more dry fire pulls. This is one of those carried often, shot little guns, so I am surprised that this might be a problem with the hand.

2. I actually only noticed it during routine dry fire during which I was slowing down to notice and changes in sight alignment during follow through. Are you saying that what I am experiencing is an artifact of the way I was dry-firing, or is it a real mechanical issue?

3. I haven't shot this gun in a couple months, so I am not sure if I am experiencing any shaving. Leading on the forcing cone looks even. Based on this information, should I sideline the gun for carry or can I still expect it to work if needed?

[LSP972]

Assuming that the gun was fitted properly during strap-up (when it was being built by a fitter), no, it shouldn't be worn enough yet. And yes, you COULD be inducing it with your trigger manipulation. Sorry, simply no way for me to tell for sure without examining the revolver.

Again, if it is not spitting, I would just shoot it. Even a J frame, when properly fitted initially, will hold up to plenty of mid-range loads; its when you feed one the hot stuff that things start to go south.

Regarding shaving… a small amount of that is to expected, and of no concern. Trust me, when it gets bad, you'll know.

.

[BN]

Is this one of the newer guns with the newer ratchet? If so, I think you need to have spent cases in it to check for carry up. I'm not sure.

[Sal Picante]

Unfortunately, I have zero clue how the MIM parts wear together. On the old system, with all milled/forged parts, the hand ALWAYS wore faster than the ratchets. This is why a serious PPC shooter would find the ideal hand width for his action, then have that puppy Armolloyed so it would not wear out too fast. But keep in mind, we're talking about tens of thousands of rounds before this became an issue. Easily attainable; in 1988, I fired over 85,000 wadcutters alone through my bull gun.

I wore the hand out on my K-22 Masterpiece... I used to dry fire that guy a lot.
Why? Because I was new and (still am) an idiot and the 686 stayed loaded.

The cylinder was much heavier than the the related .38 - only 6 holes too - the poor timing hand killed itself over the two years I had it.
I'd get shavings so bad... But hell, I didn't know that was bad...

I shot a pallet of Federal Std Vel trying to get good at the PPC game!

I miss that gun a lot... I traded it to the Capt. of the Carpentersville PD for a newer S&W 22... Didn't like.

[LSP972]

Is this one of the newer guns with the newer ratchet? If so, I think you need to have spent cases in it to check for carry up. I'm not sure.

You know, I didn't think of that. You may be right; the curved ends of the star are SUPPOSED to keep it immobilized (like the pins did on the old models); and those MIM extractors have a flat spot along the shaft that keys into a matching flat surface in the cylinder center bore. But you never know.

In any event, I'll stand by my earlier diagnosis; Nephrology has nothing to worry about and should keep shooting his J frame.

.

[Nephrology]

Is this one of the newer guns with the newer ratchet? If so, I think you need to have spent cases in it to check for carry up. I'm not sure.

Yes, it is - 2005 manufacture. I can check again with spent brass when I am back at my place.

[jh9]

You know, I didn't think of that. You may be right; the curved ends of the star are SUPPOSED to keep it immobilized (like the pins did on the old models); and those MIM extractors have a flat spot along the shaft that keys into a matching flat surface in the cylinder center bore. But you never know.

.

I think Bill's right. With the new extractor there's still some wiggle. Not much, but some. Some won't carry up without empties in it, some will. If I can get the cylinder stop to click in at 3/4 cock with spent brass and a slow DA pull I'm happy, regardless of how it behaves on an empty cylinder.