686+ Trigger Pull Issue

[Riomouse911]

Hey all,

I took out the 686+ 4" yesterday and fired about 70 .38 Spl and 14 .357 rounds through it. Groups were working out very well for me, then I had a wonky trigger pull issue. For info; the gun is stock. There has been nothing done to the gun except bead blasting, and that was done 13-14 years ago. The internals were cleaned after the finish was done and I have fired it hundreds of times, so there isn't any grit inside the action. It does have the lock, but I have never used it.

As I fired the final two .38 rounds all was fine, then he gun's trigger would BARELY pull. I literally had to take my off hand and push the top of the cylinder to get the cylinder to turn, then it fired. I fired two more rounds, then it did it again. Ultimately I set it aside and shot something else.

When I got home I put the u-tube clips on about the internals of the modern S&W, and then removed the sideplate. I noticed the sideplate screws were in their spots but neither one was tight at all, but ithe sideplate did look to be fitted against the frame tightly. When I got the sideplate off the hammer block seemed to be out of place (It could have ridden out from it's position when I lifted the sideplate, I don't know.)

I wiped down what I could, visually checked the function compared to the gunsmith videos, and all looked good. I then reinstalled the hammer block to it's correct spot after a light lube. I tightened the sideplate screws and reinstalled the grip and then pulled the trigger DA about 50 times. I had no further goofy trigger pulls.

My question is; could the looseness of the sideplate screws allow the middle of the sideplate to flex enough to allow the hammer block to fall out of place and cause this issue, or do you think is it something else that is going to pop up again when I am firing away with it?

Thanks!

Stay safe!

 

[alfsauve]

When you turned the cylinder by hand did it drag or was it easy to turn?

If it dragged then it was possibly a primer backed out.

If the cylinder turned easily by hand then it would be the internals I'd be looking at.

 

[Col. Harrumph]

If I read you correctly, the problem was that something was interfering with cylinder rotation. It's possible that a couple of bullets stayed more or less in place, unseating themselves as the gun recoiled. Then when its turn comes up, such a bullet will catch its nose on the edge of the forcing cone.

 

[Riomouse911]

I thought about that, but these were .38 spl. that I loaded myself. I use a Lee hand primer to seat one primer at a time so I don’t think it was the primers. I crimp the loads well because I remember having bullets jump a crimp once with .44 Spl and I now make it a point to check each round. I still have some unfired rounds in the range bag so I’ll double check both to make sure.

I frites two shots, then it bound up. The cylinder turned using just a finger on my left hand. The next round fired, then it turned normally for the next shot, then drug again and needed to be assisted again. That’s when I thought it may be internal because none of the previous 70-odd Spl loads acted up.

Oh the mystery

Thanks for responding!

 

[BBBBill]

If the side plate screws were loose it suggests that someone has been into the guts to possibly do some tuning. Perhaps it was "over tuned", removing too much from one or more fitted mating surfaces. An S&W is not an old style Colt in complexity, but there are still many multipurpose parts with multiple mating surfaces and critical fit to enable correct function.

Since each chamber/ratchet pad/locking notch is a tiny bit different from the others (normal production machining tolerances) one or two chambers might be the source of the problem. Might be informative to temporarily mark or number each chamber and test fire while observing to see if it is the same chamber(s) each time. Perhaps a sharp eyed observer standing to the side and watching the cylinder closely might see something. If that proves to be the case it will help you further isolate the problem. A slightly bent yoke can sometimes cause erratic function on some chambers. Even the cylinder stop can cause some issues if it is improperly fit or worn.

I presume this is the new style with V grooved yoke slot and spring loaded yoke retainer. If it is the old style note that the yoke screw is identical to the lower rear side plate screw except that the tip is hand fitted to the yoke slot, so it must be returned to the same hole.

 

[Riomouse911]

Sounds good, I’ll mark them all and shoot it a bunch to see if it’s specific cylinders every time.

The guts were taken out and then replaced when it was bead blasted so all the media could be blown out. I don’t recall the armorer who did it saying any stoning or tuning was done to the action, but that is a possibility.

If it happens again I think I’ll send it back to S&W and pay for a repair.

(The side plate screws appeared identical, and the bottom yoke screw had the pointed black tip. I did the Brownells trick and drew the side plate on a piece of cardboard and put the screws into the same spots they were taken from so I wouldn’t mix them up.).

Stay safe!

 

[JRadice45]

Did you check for powder / residue under the extractor? Depending on your load you could be getting buildup under the extractor which can cause the binding you describe.

 

[LoonWulf]

It sounds likely the side plate being loose allowed something to miss align and drag.

 

[Riomouse911]

Yesterday I checked the fired cases for raised primers and all were good, so that’s out as a cause. I cycled it again another 50-60 times and no drag. I think I’ll shoot it next friday and see if the issue returns.

I also cleaned it good so the extractor star should be good to go. I didn’t see anything that stood out, but I’ll bet it doesn’t take much to lift it out of whack and bind it up.

Thanks for all the responses!

 

[Riomouse911]

I took it out today and fired it using 158 gr FP plated reloads and then unplated lead 158 SWC reloads.

It fired the first 35 to 40-odd shots without a hitch. Then it started getting occasionally stiff again, and then bound up completely. No unfired bullets were protruding out from the cases and all primers we’re not raised on the fired cases in the cylinder when it quit.

You can see the goofy flyers starting to hit low and then way off to the right from the trigger beginning to bind on the target, which is a reduced scale US Treasury Dept silhouette I was shooting at 10 yds.

I’ll be calling S&W on Monday for a return label and I’ll ship it back to be fixed.

Thanks again for the responses!

Stay safe!

 

[mcb]

Check that the ejector rod has not gotten loose and unscrewed.

 

[shell70634]

Check extractor alignment pins. Had a 686 with same problem. One pin was missing

 

[Riomouse911]

All in the cylinder is good and the rod tight and nothing looks askew...I had that exact problem when I bought the used M-13. That one did have a loose ejector rod, and it bound up the action and wouldn't let it open. No issues with this opening and closing (so far!)

One thing I noticed with these 7-shot Smiths is the extractor star has a couple of angled cuts that mesh perfectly with the ones on the cylinder so it can only be installed in one position. The angled ones are to the bottom, and the straight-across cuts are at the top. (Forgive the blurry pics, they all looked better on the phone screen!)

I didn't see any pins under the extractor like my M-13 has (Middle and Bottom pics). It all seems to line up well and nothing can overhang a charge hole without an arm being bent.

I'm stumped. I swear the recoil is knocking the hammer block loose inside the action and it's getting hung up against the frame. It acts like something is floating around in there loose and it acts up only after a batch of rounds have been fired.

Oh well, off to S&W it goes!

Thanks again for all the responses, you guys are the best. When I get an answer from S&W I'll update.

Stay safe!

 

[RecoilRob]

Did you happen to check the barrel/cylinder gap? Tight is good for reduced leakage but can cause binding when it gets warm and dirty from shooting. I've had several wheelguns like that....went several cylinders full without problems but then started to get sticky. Let them cool down and were fine for some more shooting. If you want to be able to fire lots and lots of rounds you might need to enlarge the gap a bit to allow for the expansion that will take place.

 

[4v50 Gary]

Removal of the sideplate (by tapping on the grip with the handle of a screwdriver or mallet) can dislodge the hammer block from its place atop the rebound slide. I wouldn't worry about it.

I'm wondering if the cylinder stop wasn't dropping, thereby preventing the cylinder from rotating?

 

[WrongHanded]

Having had this problem myself, have you checked the B/C gap? I had a revolver with a very tight gap, and once the gun got dirty, it started to bind. Intermittently.

 

[Riomouse911]

That BC gap could be it. I didn’t see any scratches or other obvious marks on the front of the cylinder, but it sure could be the reason it binds up only after shooting a handful of rounds...

I called and got a shipping label from S&W today. I’ll be heading out for a motorcycle race in the morning, I’ll be dropping it off at fed ex in Lake Havasu Az tomorrow... if I get there before they close!

Stay safe.

 

[boom boom]

That BC gap could be it. I didn’t see any scratches or other obvious marks on the front of the cylinder, but it sure could be the reason it binds up only after shooting a handful of rounds...

I called and got a shipping label from S&W today. I’ll be heading out for a motorcycle race in the morning, I’ll be dropping it off at fed ex in Lake Havasu Az tomorrow... if I get there before they close!

Stay safe.

You can check the barrel/cylinder gap yourself with cheap feeler gages picked up at any auto parts store or some hardware stores. Pretty useful to have on hand.

 

[4v50 Gary]

What BoomBoom suggested. We used feeler gauges to determine it.

 

[Clemson]

If someone has backed out the strain screw too far, that mainspring can knuckle and create the problem that you are describing. The solution is to keep the strain screw seated all the way in. If it has been shortened, it needs to be replaced.

Bill Jacobs

 

[Riomouse911]

It’s enroute to Springfield Ma. Via Fed Ex, so I’ll find out what the issue is and let you know.

Thanks again for all the responses!

Stay safe!

 

[Riomouse911]

Well, I got the 686+ back today, the shipping notes said they replaced the extractor and “fixed the yoke.”

I am not a cylinder-snapper so I have no idea what the yoke issue was. I’ll take it down to the range on Friday and see if I can get it to act up again. Hopefully all is fixed and its good for another decade or two before any further adjustments.

I’ll check the b/c gap when I get home and post that.

Thanks for the suggestions, stay safe!

 

[Riomouse911]

Just checked the b/c gap with the Craftsman feelers... it’s .004” all the way around. A bit tight, but not the tightest one I’ve seen.

Stay safe!