Mk III trigger issue

Help Support Ruger Forum:

pfisher

Bearcat
Joined
May 23, 2010
Messages
4
Location
Scottsdale, Arizona
Hi all,

New member here. This may have been covered before but I've spent most of the afternoon looking for the answer and I'm not sure about what I've found so bare with me. I just picked up a new Ruger Mk III Competition and it's been having a problem right out of the box with failures to reset the trigger. The bolt seems to be cycling properly as I'm not having any ejection or feed issues. What is happening is that quite often the pistol is not resetting the trigger. I've been able to determine that when this happens if I press the mag release and pull the mag out slightly, say .25 inch, then I can see the trigger return to it's full forward position and it'll be ready to fire.

I did find some posts about this problem but I'm totally lost when it comes to firearm internals so I'm not sure about what I read. I did remove the upper to look at the trigger mechanism. I found that if I pushed down on the disconnector the trigger would move through it's full range of movement but if the disconnector was up the trigger wouldn't move. I don't know if that's what's happening when shooting but it sure feels the same through the trigger.

Anyone care to enlighten this "idiot"? What might be happening internally to keep the trigger from resetting after a shot? Why would dropping the mag a fraction of an inch allow the trigger to return to it's forward position? Thanks in advance and beers on me for whoever can answer my questions.
 

Geezer

Single-Sixer
Joined
Mar 13, 2009
Messages
249
Location
Conway, SC
Yep, the magazine disconnect. Replace it with a MK II hammer bushing and your sticky problem will be solved and your trigger pull will improve.
 

pfisher

Bearcat
Joined
May 23, 2010
Messages
4
Location
Scottsdale, Arizona
Thanks to Geezer and Slow for the responses. I ended up removing the magazine safety and thought I'd relate my experience. I also have a question at the end for anyone who's quite familiar with MkII's and Mk III's.

Items used for this mod:

1 - bench grinder
1 - set of jewelers files
2 - M5 washers
1 - SAE10 washer
Snake oil lube
Gun Slick

First I watched several youtube videos the detailed how to remove the part. It seemed pretty straight forward so gave it a try. Keep in mind I've never disassembled any firearm other than removing bolts, barrels, slides, ...etc.

Disassembly went smoothly up to the point of removing the hammer pivot pin. I tried to remove the hammer and bushing assembly without totally removing the hammer pivot as recommended but just as I had only about a millimeter more to pull, all resistance on the pin vanished and it popped right out. CRAP!! After a quick review, things didn't look too bad and it was actually very easy to replace the safety and slide lock lever. Ok, back in business (or so I thought. More about this shortly).

Next came the really time consuming phase. I had picked up several M5 and SAE 10 washers as recommend in a some videos. As expected I had to open up the M5 washers slightly which is where the jewelers files came in handy. Just a couple minutes effort was all that was needed for both M5 washers. This is where my experience differs from the video I was emulating. I could not use two M5 washers and one SAE 10 washer. There wasn't enough room in the frame. After some checking I settled on 1 of each. This seemed to work so I buttoned everything up and was about to try cycling the bolt when, OH CRAP!!, what's this little spring doing laying on the table.

Turns out it was the sear spring. At some point, probably when I accidently pulled the hammer pivot completely out, the sear pin just fell right out. After about 10 minutes looking for a good online exploded diagram of a Mk III it only took about another 5-10 minutes to get the sear re-installed. That actually wasn't nearly as bad I was expecting. So I buttoned everything back up a second time and tried cycling the bolt several times. Hmmm. There seemed to be a problem. The hammer wasn't being cocked. So I had to disassemble it once again.

After carefully checking the my previous handy work I determined that the SAE 10 washer was too big and was preventing the sear from locking up with the hammer. So out came the hammer and the two washers so I could try grinding down the 10. I used the bench grinder for this. However, by the time I had ground down the outside diameter of the 10 washer I was left with what was basically a hacked up M5 washer. So I pitched the 10 and worked over another M5 to use. I installed both M5's and buttoned everything back up. Now the pistol appears to work as expected with less effort being needed to pull the bolt and the trigger seems, while not lighter, to break more crisply.

Now for the question. While I was cleaning up I found a small piece of metal that appears to be the LockDetent Plunger. Below is a link to an online copy of the Mk III manual and the LDP is number 55 in the exploded diagram. I can't really see how this part goes into the main spring housing. Can anyone provide some insight? And no, I didn't find the spring that accompanies it.

http://www.scribd.com/doc/8413154/Ruger ... ion-Manual

So, there you have it. Total time was about 3 hours but with most of that being used to shape and modify the darned washers. I think though that I'm going to order a Mk II hammer and bushing so I can get rid of the washers. I figure each face of the washers just adds unnecessary friction to the internal workings. Fyi, I used the Snake Oil on the washers and hammer bushing to prevent the extra friction. I'll take it to the range, Rio Salado, on Friday or Saturday and will report my findings.

Now, I just need to figure out how to attach a picture of my III for a little eye candy for anyone interested.

Btw, thanks again to Slow and Geezer,
Fisher
snc00331600x450.jpg
 

Geezer

Single-Sixer
Joined
Mar 13, 2009
Messages
249
Location
Conway, SC
Does your safety "click" in the on or off position? There is a small plunger that goes on the safety.

Unless you have damaged your hammer, all you need is a MK II hammer bushing. I think I may have a couple around here somewhere. $20 shipped, PM if interested.
 

pfisher

Bearcat
Joined
May 23, 2010
Messages
4
Location
Scottsdale, Arizona
Yep, that was it. I've replaced the safety tab and everything appears ready to test this weekend. Thanks, I never would've thought to check the safety.
 

CraigK49

Bearcat
Joined
Sep 18, 2010
Messages
8
Location
Arizona
Saw the same videos and was about ready to go the the washer store (Home Depot) when I saw that replacing the hammer bushing from a MKII would accomplish the same thing. I ordered a Volquartsen Mark II Hammer Bushing from www.rimfiresports.com for the princely sum of $7.95 including shipping.

To me it was a no-brainer. For less than $8.00 I'm getting a precision machined and hardened bushing (closer tolerances than factory) instead of a couple of washers jingling around in the innards of my 22/45 that have to be hand trimmed and ground to fit "close enough."

I'll post the results when I get the bushing. I hope this will save someone from ending up with a non-functioning or malfunctioning MKIII. Time will tell if I can make the mod without any spare parts left on the bench. :wink:
 

Yosemite Sam

Hunter
Joined
Mar 18, 2002
Messages
2,113
Location
Cape Cod, MA, USA
I've been talking about my own over on RFC lately, but I did a similar upgrade. I put in a MkII bushing, and a VQ sear and trigger. Bushing is definitely worth the upgrade. The other parts will have to prove themselves. I don't notice much difference at all with the sear, and because of the way the mechanism works, you can't adjust out very much of the pre- or over-travel from the trigger.

-- Sam
 

pfisher

Bearcat
Joined
May 23, 2010
Messages
4
Location
Scottsdale, Arizona
I ended up doing the same as CraigK. I wasn't happy with the feel of the washers so I picked up a new MkII hammer bushing and a Volquartsen hammer and installed those. This is definitely better but since I like to tinker with things I tried the washer route first. One side benefit, for me at least, was I learned a lot. This MkIII is the first pistol I've worked on myself so it was a worthwhile exercise.
 

cbuxton41

Bearcat
Joined
May 26, 2008
Messages
17
Location
Derry, New Hampshire
Yosemite Sam said:
I've been talking about my own over on RFC lately, but I did a similar upgrade. I put in a MkII bushing, and a VQ sear and trigger. Bushing is definitely worth the upgrade. The other parts will have to prove themselves. I don't notice much difference at all with the sear, and because of the way the mechanism works, you can't adjust out very much of the pre- or over-travel from the trigger.

-- Sam
Very interesting...where does the Mark II hammer bushing go in the gun? Right or left side of the hammer??? Does it replace the existing hammer bushing or is it an addition? :oops:
Thank you
 

CraigK49

Bearcat
Joined
Sep 18, 2010
Messages
8
Location
Arizona
This is a followup to my Sept 27th post. The installation of the MKII Hammer Bushing was almost a non-event. That means I spent a lot of time worrying that it would take hours and multiple attempts to get my pistol back together.

The actual time was probably about 15 minutes give or take. After taking it down to the equivalent of field strip, I used an appropriate drift to push the hammer pivot pin in far enough to remove the hammer/bushing/magazine safety.

The original bushing and magazine safety come out very easily. The new bushing is inserted into the hammer and goes back into the frame in the same order it was removed.

I saved the MKIII bushing and magazine safety just in case I need to return it to stock condition. (cbuxton41 - the MKII bushing replaces the MKIII bushing)

The illustrations and instructions over at http://guntalk-online.com/2245detailstripping.htm were a great help. I highly recommend studying the information there before trying to make this (or any other) modification.

Reassembly from there was a snap. No more magazine insertions and removals to go from field stripped to assembled condition. And the magazine zips out when the magazine release is pressed just like it is "supposed" to.

Haven't had the chance to shoot it, but may be able to do that this afternoon. However the trigger feels great and I'm pleased with the results so far. :D
 

cbuxton41

Bearcat
Joined
May 26, 2008
Messages
17
Location
Derry, New Hampshire
Craig,
Thank you for your clarifying post. I hope the mods work well for you.
I have the Mark II hammer bushing, Volquartsen trigger and sear on order. I hope I can be as adroit as you at getting it all installed. At my age (69) my eyesight, manual dexterity, and patience are somewhat diminished.
I have read posts on other forums about removal of the magazine safety and they say you should also replace the Mark III hammer with a Mark II hammer as well as the hammer bushing. Any validity to this?
Thanks again. :idea:
 

CraigK49

Bearcat
Joined
Sep 18, 2010
Messages
8
Location
Arizona
I have read posts on other forums about removal of the magazine safety and they say you should also replace the Mark III hammer with a Mark II hammer as well as the hammer bushing. Any validity to this?

cbuxton41

The difference between the MKII and MarkIII hammer is a cut out on the right side. This creates a lip that the magazine safety uses to block the hammer when the magazine is not present.

The MKII bushing has a lip that covers the cut out. So, the only real difference is the MKII hammer might be a gram (+/-) heavier. I don't think this would change anything since the additional weight is absent from the pivoting end where it would have the least effect on the moving mass.

At least one after-market hammer has holes drilled in it to reduce mass. So, the small amount of metal missing on the MKIII is of no real consequence. At least in terms of the hammer function. At the very least, the reduced mass may increase hammer speed very (I mean veeeeery) slightly. Think of how much your car slows down when a fly hits the windshield at 60. Maybe on the order of three flies at the same instant...
 
Top