Ruger Service-Six issue


March 8, 2010, 05:08 PM
This one is for all you Ruger experts out there. I have an older (1977) 4" Police Service-Six that I've had for 20+ years. I've shot it very little, it's main role is as a stashed house gun stuffed with .38 +p's. It has developed an issue and I'm hoping someone on here can point me in the right direction before I haul it off to a gunsmith.

I can pick it up and cycle it as many times as I want in both single and double action and it operates perfectly. However when I actually fire it, even with mild .38 reloads, it "locks up" until I take my weak hand and "wiggle" the cylinder. (The cylinder is not loose, the wiggle is minuscule, about what ALL revolvers will move) By locks up, I mean I cannot move the hammer back more than about 1/8" and if I try a double action trigger pull, the hammer will again move about the same 1/8" inch and everything stops at that point.

I have tried to gently force the issue to no avail. I'm hesitant to pull too hard on either the hammer or the trigger because I really don't want to damage anything. All that will make the hammer free up is the aforementioned cylinder wiggle. I have looked as closely as possible when wiggling the cylinder to see if I can tell what's being freed by that movement and I can see nothing. I have also looked closely at the bolt stop because logic tells me that is the part most affected by the cylinder movement and all seems to be well.

After I fire a shot and wiggle the cylinder the action is again free for as long as I care to cycle it until that next round is fired. I'm at about my wits end with this one. If there is anyone out there who has seen or dealt with this in the past, I would be most grateful for your comments.

If you enjoyed reading about "Ruger Service-Six issue" here in archive, you'll LOVE our community. Come join today for the full version!
March 8, 2010, 06:15 PM
when ya fire it watch the cyl latch at the bottom of the frame window it supposed to start movin when ya move te trigger /via trigger or hammer.

If not probably the spring that resets the trigger is weak.

March 8, 2010, 07:22 PM
Make sure the ejector-rod assembly is screwed-together tightly.

If it is coming unscrewed, and you are unaware, it will tie up a revolver.

I think Ruger ejector rod threads are left-hand thread (righty-loosey).

March 8, 2010, 09:08 PM
always start looking at the simple stuff.

1. check tightness of the ejection rod
2. check under the ejection star for dirt/powder
3. clean the face of your cylinder (this is what i think it is) and the rear of the barrel

is it happening on all cylinders or only on certain cylinders?

March 8, 2010, 09:57 PM
always start looking at the simple stuff.
I've been thru it looking for exactly that kind of stuff. It's not a cylinder rotation issue, the hammer locks before the cylinder ever tries to start rotation. Everything is clean, tight, and works exactly like it should UNTIL you fire a round. If it were doing it all the time, it would be a little simpler to find. And once it locks and you wiggle the cylinder, it works again freely until you bust off another one........

March 8, 2010, 10:46 PM
I'm thinking dried goop in the mechanism.

If the ejector-rod has not self-unscrewed itself, I would take the grips off and inject the innards with mass quantities of Break-Free.

Then work the mechanism until it loosens up.

March 8, 2010, 10:57 PM
is the hand rising and catching on the star or is it not even making it that far before it locks up?

what's throwing me is that you can free it up by wiggling the cylinder...that just screams ejector rod, hand or star

March 8, 2010, 11:55 PM
Check if the screw underneath the cylinderlatch is tightened.

March 9, 2010, 02:19 AM
Sometimes this happens with very weak loads and blanks. Upon ignition primer backs out of its pocket (this is normal) but there isn't enough recoil force to reseat it and it locks the cylinder. Check to see if primers are high after the rounds were fired.

If you have same problem with full power rounds, then I would check for dirt inside firing pin housing or weak/broken firing pin spring that prevents it from backing out after the shot.


March 9, 2010, 09:54 AM
is the hand rising and catching on the star or is it not even making it that far before it locks up?
I can't tell for sure with the cylinder closed, but I don't think it's even making it that far. It's NOT an issue with the cylinder binding, the hammer only moves about 1/8" and locks well before any other action movement starts to take place. I've opened the cylinder and depressed the little button in the center that causes the cylinder latch to pop back out to fool it into thinking the cylinder is closed and then watched the action. Nothing has started to move by the time the hammer gets to the place it normally locks up.

Hoptob, I did hold it up to the sun and look thru the gap between the case head and the frame and the pin had retracted as it should have.

To all the folks talking about loose rods and cleaning it...I do appreciate the offers of advice, but please understand that it only locks up immediately after I fire a round, be it a mild .38 of a full house magnum. There is no binding, no sticky mechanisms, no loose rods, no dirty areas and once I free it, it works perfectly time and again until I fire another round. I think that part of the problem is being overlooked in some of the responses. And that's the part of this that's driving me crazy...(ok, crazier ;))

If it were dirty or loose or whatever it would do it all the time and THAT problem I could find. I think at this point I'm going to break it completely down and replace every spring in it. In circuit board repair that's known as a shotgun fix :D
If that doesn't do it, it's off to a smith. I can't depend on it as it is, and my conscience won't let me sell it like it is now. Got to do *something*.

Again, thanks to each and every one of you who took the time and effort to respond. I do appreciate it.

March 9, 2010, 10:07 AM
Let us know what you find.

If the ejector rod aint loose, I still think a Break-Free enema will have it feeling fit as a fiddle in short order.

March 9, 2010, 10:27 AM
I'd take a really good look at the pawl that locks the cylinder. That would be my second look due to the fact that if you shock it with a round, it may be "cocking" in it's groove. Good luck! BTW- Wolff Springs has a great kit for this gun, and you can replace them yourself......:D

March 9, 2010, 12:49 PM
Is the firing pin retracting when you let the trigger reset?

March 9, 2010, 01:24 PM
it's just one of the inherent problems of the Ruger design...there isn't a sideplate to remove so that you can actually see everything interacting while the action is in motion

March 9, 2010, 02:01 PM
Ruger still services those, might consider returning it to them.

March 9, 2010, 02:08 PM
Check if the screw underneath the cylinder latch is tightened.

Or the firing pin is not retracting on it own, broken spring maybe?

Edit: After looking at one of my Security Sixes I believe it's most likely the firing pin not retracting. When you try to pull the trigger again it drags against the primer until it catches the edge of the primer pocket and locks up the gun. Wiggling the cylinder probably losens it up enough to fire again.
When dry firing it has nothing to catch onto and the gun cycles fine.

March 9, 2010, 05:49 PM
Check if the screw underneath the cylinder latch is tightened.
PzGren, you nailed it. When I first read your post, I misread what you were referring to. I thought you were talking about the screw that holds the cylinder latch in place, like a S&W has and dismissed it as you not even being familiar enough with this model to know what you were talking about because Ruger doesn't use those. Now I feel like a total dumba** :o

After I disassembled it, I got a strong light and started inspecting the parts and as I was looking at that area, I realized that I could see threads from that set screw showing. I took a jewelers screwdriver and it took about 4 turns to get snug again. I just walked down to my range and ran a few cylinders thru it and all works perfectly. Not only did I get it fixed, I learned a lesson about paying more attention to the responses that I came on here and asked for.

Thanks again to everyone. Now I'm off to eat a little humble pie.......

March 9, 2010, 06:12 PM
I had one lockup on me before. It was caused by cleaning the gun years ago with WD-40, before I new better, and letting it set in the safe for several years.
I completely stripped the gun, cleaned and lube it with clp and it works fine now.

March 9, 2010, 06:41 PM
I've read the posts, and I still don't follow as to what screw is being described.

Got pics?

Which part # are we talking about?

Blue Brick
March 9, 2010, 06:43 PM
I use a very light coat of Moly Lube.

March 9, 2010, 07:04 PM
Which part # are we talking about?
KE-27. Little bugger of a set screw that holds the cylinder latch (E-9) in place.

March 9, 2010, 07:11 PM
when you answered so quickly, we just figured you'd already checked it :)

March 9, 2010, 07:12 PM
Your description sounds an awful lot like binding. If the gun functions fine while unloaded, then it must have something to do with the the ammo.

If it's binding, the first thing to find out is where it's binding.

Please measure your barrel/cylinder gap. If the blast is heating up the cylinder or if powder is building up on the cylinder, you could get cylinder binding.

Second, please measure the headspace (between the case and the backstrap). If the space is too small, binding will occur on the case heads.

B/C gap should be between .004 and .009-inches. The headspace should be between .006 and .009.

Again, the problem seems to be binding. Find out wher it's binding and go from there. If it's binding in the back, that will require a gunsmith. If it's binding in the front, you can open up the cylinder gap yourself.

March 9, 2010, 11:42 PM
I had this problem with a SP101 a few years ago and it drove me nuts! It wasn't too bad but in double action there was a considerable drag and inconsistent trigger pull. At first I thought that the transfer bar was to be blamed and disassembled the gun, polished the bar, checked the pawl (Ruger doesn't call it a hand), and about any other moving part.

It was much later that I just sat down, had a couple of cold ones, and really looked at the gun, trying its functions. After noticing that the trigger pull got normal when I slightly held the cylinder latch during the trigger pull, I had found the problem.

The problem of binding on Rugers was described on several boards and my answer usually disregarded, so I just got down to a one sentence answer in this post:).

I rust blued a Service Six a few years ago and had to completely disassemble it, and believe me! I gave special attention to that little screw when it went back in.

March 9, 2010, 11:58 PM
Roger that on the set-screw!

I just pulled my Security-Six out of the leather, and it looks like I'm OK.
In fact, it you look closely in the pic, you can see the screw is STAKED at 12 o-clock as the screw is positioned in the pic.

I'll know what to look for if the problem ever pops up.

If you enjoyed reading about "Ruger Service-Six issue" here in archive, you'll LOVE our community. Come join today for the full version!