HELP! Ruger MK1 trigger issue

[superdavebigd]

My 1970's River Mk1 heavy barrel will not fire with mag inserted. I pull the trigger, it goes 1/2 or 3/4 the way back but does not fire at all, nothing happens not even a click.

I bought the gun recently, it is in excellent condition overall. It worked great the the first time out, but has gradually gotten worse every time out (like 5) and now won't fire.

If I remove the mag it fires like normal.

Only change I have made was tuning the magazine feed lips to better hold/feed the ammo. Please help a brotha out. Thank you!

EDIT: After playing with it more, I found the issue happens with or without mag inserted. This was in my home, so no ammo was in the magazine. It was 100% failing with a loaded mag at the range.

[TRAP55]

My best guess would be the mag is causing some kind of interference with the disconnector. Do you only have the one mag to try in it?

http://stevespages.com/ipb-ruger-mki.html

http://stevespages.com/pdf/ruger_mki.pdf

[superdavebigd]

Yes I tried 2 mags. I just recalled, my buddy has a mk1 and he let me try his mag with no change. I appreciate the help.

[OldAudioNerd]

I'd join up at rimfirecentral.com and ask there too. That place is a wealth of knowledge

[Chaos47]

Hard to say without taking it apart and inspecting it..

Ideas:
Something is wrong with the trigger/plunger/spring (or if it has an adjustable trigger the screws have moved)
Something is wrong with the disconnector bar
Something is wrong with the safety (partially engaging) (Sounds odd but I've had my MKI slip down to a mid position which would make the trigger go dead)
Something is wrong with the hammer/sear
Something is wrong with the mainspring

[TKM]

Sometimes the sear pin will drift a little, changes the engagement angle. Are all of the pins flush?

[nedro]

First things first.
Take it apart completely, clean, reassemble.
Another thing. Don't tweak the feed lips on a mark. If you have mag issues, clean and polish the mags. Although self explanatory, rimfirecentral has a thread on it.
I had this issue with an adjustable trigger. Make sure the trigger is resetting. when it won't fire, try pushing the trigger forward and listen for the reset click. If that's happening, go back to my first suggestion.
If your mark has a mag disconnect, get the bushing and remove it.

[superdavebigd]

Wow this forum is awesome. Thank you all for the ideas. I also started a thread on rimfirecentral in the MK1 section.

It is not a trigger reset issue. Tried that, and been through that before on another gun.

I will report back in a day or two after disassembling/cleaning and inspecting all parts. Will take some photos of the parts too.

[superdavebigd]

Photo attached of ma baby.

[superdavebigd]

Found the problem. Thanks to members here and on rimfire.

The Hammer Pin walked completely out of one side. I attached a photo. This was due to the Hogue grips the previous owner put on. There is supposed to be an insert to stop the pin from walking out.

Hammer drops 100% time now with snap caps, still have to field test it.

[Chaos47]

Glad you figured it out

[Fatcat]

That was easy fix! Sometime the disconnector will get tweaked from a frustrated owner and when it gets reassembled, the disconnector will drag and prevent the hammer from falling. If your ever strip the lower down for cleaning, take your time and have patience.
Here's a link to a job aid over on the Gun-talk forum for Mkii, iii, and 22/45 diassembly,reassembly.

http://guntalk-online.com/detailstrip.htm