Cylinder latch not holding cylinder in place

[bcfryer]

Suggestions , New to me Ruger GP100 , with cylinder closed and trigger released and hammer at home I can turn on the cylinder enough to have the cylinder latch ride out of the notch and be pressed down as it is spring loaded. Is this normal?

[/img]. Now with the trigger pulled all the way back and the hammer up or down the lockup seems good , very little play. This is a 1988 Gp100 stainless 4" in .357 . I would like to add a picture of the revolver showing the latch , don't know how

 

[Jimbo357mag]

I'll throw my 2 cents out there. No, that is not normal. The cylinder should be fairly secure in the un-cocked position. There have been some reports here of new guns that would do that and in all cases Ruger wanted the gun back for repair. I would call Ruger and request a shipping box to return the gun for repair. It is probably just a worn cylinder latch and notches. Or you could perhaps order the latch and replace it yourself and see if that solves the problem.

 

[bcfryer]

I had the trigger assembly out this morning and was looking at what I think is wear on the end of the trigger plunger. I wonder what relationship the trigger plunger has with the cylinder latch. Should the end of the trigger plunger reside under the cylinder latch or over it? The trigger plunger tip is not full across but has a notch worn on the right tip looking down with the cylinder latch away from you.

 

[Jimbo357mag]

Can't help you there, sorry.

 

[Carry_Up]

The cylinder latch is the thumb piece that unlocks the cylinder from the frame for loading and unloading. The locking pawl, on the other hand, is the piece that locks the cylinder into position so the barrel and chambers line up correctly.

In the first case of the cylinder latch, the spring loading for that part is in the ejector assembly - something that could easily have been assembled incorrectly.

In the second case of the cylinder locking pawl not securing the cylinder from rotating, you have either a broken part, or once again incorrect assembly. Photos?

 

[Jimbo357mag]

The cylinder latch is the thumb piece that unlocks the cylinder from the frame for loading and unloading. The locking pawl, on the other hand, is the piece that locks the cylinder into position so the barrel and chambers line up correctly.

In the first case of the cylinder latch, the spring loading for that part is in the ejector assembly - something that could easily have been assembled incorrectly.

In the second case of the cylinder locking pawl not securing the cylinder from rotating, you have either a broken part, or once again incorrect assembly. Photos?

Sorry you are not using the correct Ruger terminology. Check the owner's manual.


The part that unlocks the cylinder from the frame in called the 'crane latch'.

The part that locks the cylinder from rotating is the 'cylinder latch'.

 

[JB696]

With the cylinder open, push down on the cylinder latch with your finger and see how much resistance there is. It's hard to explain exactly how firm it should feel. But if the cylinder latch spring is weak, has a couple of broken coils, or is gummed up with old grease this could be the problem. If the tip of the trigger plunger is worn or damaged the latch spring should still press the tip up into the cylinder notch enough to hold it in place.

There is another possibility easily checked. At the factory, sometimes there is a timing problem on the assembled gun. As the trigger is pulled the pawl begins turning the cylinder before the latch has pulled out all of the way from the cylinder notch. This causes a bind as the latch briefly hangs up on the edge of the cylinder notch. I correct this timing problem by installing a trigger plunger that is a few thousandths longer and a pawl that is a few thousandths shorter. This way the latch begins to retract sooner and pawl begins to turn the cylinder later. The fit of these two parts is a fine line. If the cylinder latch releases the cylinder too soon, that is, before the tip of the pawl has engaged the ratchets on the rear of the cylinder, then the cylinder is momentarily loose and can be turned backwards.

This measuring of the parts and matching them up in the best combination is very time consuming. It helps that I have a big bag of new trigger plungers, pawls and cylinder latches. But at the factory they don't have this kind of time. So what they do is pull off the trigger group and slip off the cylinder latch. Then they take a dremel and grind off the tip of the cylinder latch, on one side or sometimes both. This "bevel" can sometimes be severe. Rather than taking off a little bit of metal and putting the trigger group back in to check for binding they save time by taking off too much the first time. This can make a cylinder latch that slips out easily even if the latch spring is good.

So check the tip of your cylinder latch. Is it mostly square on the right side and slightly beveled on the left side? Or did somebody at the factory go nuts with a grinding disc because their boss was riding their ass to speed things up?

 

[bcfryer]

I looked things over again and I see this. Timing is good, cylinder latch is pushed down I guessing by the trigger plunger just before the cylinder starts to rotate and is released and then rides the surface of the cylinder until the cylinder lines the chamber to the barrel and it then under the spring tension goes back into the slot in the cylinder. looking down on the revolver with barrel pointing away from me the cylinder rotates counter clockwise. the left side of the cylinder latch is verticle with a defined edge. The right side of the cylinder latch is beveled like one took a grinder to it. The cylinder being closed may be rotated clockwise but not counter clockwise. When rotating the cylinder clockwise the beveled right side of the cylinder latch will catch slightly but can be defeated with a little turning pressure clockwise. I know on both of my other revolvers one a smith 686 and the other a colt lawman Mk111. both sides of the cylinder latch is the same. No ground off area on the right side.

 

[JB696]

We may be on to something here. When holding the gun in the firing position, the tip of the cylinder latch should have the bevel on the left hand side. All of my SP101's have the beveled edge on the left. Some of the new SP101 latches that came from Ruger have a slight bevel already ground on them. It's always on the left. The right side edge is lightly polished but I've never seen one with metal taken off there. If the one on your gun is ground off on the right side that could let the latch slide out of the notch.

If yours is indeed an oddball it should be replaced. It wouldn't hurt to replace the trigger plunger as well. The Brownell's part number for the latch is 780-000-461WB (out of stock) and the Ruger number is KH04505. The parts may not be available. But if you contact Ruger and explain the irregularity in your part they may send you another latch. Or they may send you a shipping label to send the gun to them for a free fix. I would contact Ruger customer service and check.

 

[bcfryer]

 

[bcfryer]

Finally discovered how to send a picture. See the latch edge as it is beveled. Is this wear. should a new cylinder latch be without this bevel.

 

[silverback]

bcfryer, I think it is either your cylinder latch spring or someone did some work on the latch. I checked both my gp 100's 4 and 6 inch and your latch seems to sit lower than mine. I also thought that maybe someone put an sp101 latch in there. I switched latches from the sp101 357 I have for sale and it works just the same and sits just as high. I would try a new spring first. look for the simplest fixes first. I have read that some people try to work the latch so it doesn't cause the mark on the cylinder maybe that's possible.

 

[Jimbo357mag]

That latch looks bad to me. It should not be beveled to one side. The notch on the cylinder looks fine.

 

[bcfryer]

ordering parts. Midway usa a good source? Brownells is out of some parts.

 

[silverback]

if you are going to get a trigger plunger spring might as well kit wolf's spring kit. that way it gives you options on trigger weight. midways is just as good as brownells. you might want to take a look at numrich.

 

[JB696]

The trigger plunger spring is a small one that shoves the plunger towards the step on the cylinder latch. It doesn't come as part of a reduced tension spring kit. The one in the kit you're thinking of replaces Ruger #KT03800 which is the trigger guard latch spring, which also serves as a trigger return spring. I've owned dozens of SP101's and several GP100's. In my former parts bin I had at least 50 new cylinder latches for the SP101. I've never seen one with any bevel on the right hand side. Of course, this is just my personal experience. Maybe there are some GP100 and SP101 owners here that can take a look at their cylinder latch and see if it has a right side bevel like the one in the picture.

 

[silverback]

JB696 ---- I stand corrected sir. you are referring to the pawl spring. Ok I can see why you would want to replace both the cylinder latch spring and the trigger plunger/pawl spring.

yep I don't see any bevel on the right side of any of my gp's or sp101's

 

[JB696]

No problem. It's a pawl spring too. It really gets interesting when you get over to that other forum. The S-W guys call the pawl a "hand". :roll:

 

[bcfryer]

Here are a few more pictures of the trigger plunger and the cylinder latch. Wolf springs , do they add much to a smooth trigger pull ?

http://i1313.photobucket.com/albums...8-a8d9-4ba7-b333-321ad76444f6_zpsf08c4516.jpg

http://i1313.photobucket.com/albums...a-32e5-4ec7-bbef-20e453c3f58e_zpsc480697d.jpg


http://i1313.photobucket.com/albums...3-1c49-4782-a9a1-3610ba3e2dc3_zpsa47abf43.jpg

 

[JB696]

Yes, a spring kit will help. Everyone here probably has their preferred spring combination. The usual process is to go lighter on the springs while shooting an assortment of ammo/primers until there is a misfire from a light strike. Then go a step or two heavier on the springs to ensure reliable ignition under all conditions. The very light springs are good on a target gun. But there is nothing as embarrassing as a misfire in a critical situation. On my Sp101's I leave the stock spring in the trigger guard because I like a firm trigger return. On the main spring I go with a Wolff #10 ten pounder. Thousands of rounds fired, no misfires. Of course, this is my personal choice. Your particular gun and your mileage may vary.