Need help diagnosing MK ii FTF issue.

[platapus]

Hello, first post from a new member. I picked up a Ruger MK ii with a 8 1/2" Paclite upper receiver. I took the pistol apart for a thorough cleaning and reassembled. This pistol has every bell and whistle. Match trigger, target grips, and adjustable target sights. If you don't have the barrel pointed upwards when charging, it will not fire. It will also have a failure to charge after every 3-4 rounds. The trigger is not being cocked unless the barrel is pointing upwards when charging. I don't get it. Another thing that happened is when I inserted an fresh magazine and depressed the slide release, then pistol fired on it's own. Good thing I had it pointed in a safe direction. I would say that this pistol only had around 500 rounds out of it. Can someone please help me trouble shoot this issue. I am not a master gunsmith but work on several ar-15's that I own and can strip a semi auto pistol and reassemble. I can provide info if I am not explaining the issue sufficient enough.

Thanks for the help,

 

[Bullseye57]

Sounds to me that the sear spring is not returning the sear back against the hammer hook. When tilted barrel upward the sear is falling back against the hammer by gravity and cocking the hammer. When the bolt is open, the hammer is held back until the slide is released, then the hammer follows the bolt home and contacts the firing pin. Check to ensure that the end of the sear spring is in behind the frame crosspin, this is done by removing the mainspring housing and inspecting in the mainspring cavity on the left hand side of the frame. If it is then the sear spring may not be properly place on the sear and to fix that would require a detail stripping.

R,
Bullseye

 

[platapus]

Thanks Bullseye. I have taken the pistol completely apart and reassembled doing a thourough inspection. I have even watched several videos on YouTube. I don't know what the heck I'm doing wrong. What it boils down to is that when I go to close the main spring there is the little bit of tension missing before closing the mainspring latch. I know it's probably something simple but I am beside myself. Please help point out where I'm failing.

Thank you,

 

[Dan in MI]

I defer to Bullsye's knowledge and experience, but I am wondering if all of the work done prior to your ownership is a clue.

Bad trigger job?

Overtravel screw out to far to prevent a good reset?

 

[Bullseye57]

It is very possible that this gun could suffer from an over-zealous trigger job. If that's the case replacing the hammer and sear may be the only remedy to solve the problem. In any case be sure to test the firearm, at a range, with no more than two rounds in the magazine until you're absolutely certain the trigger system is functioning properly.

Not all Ruger .22's have the tension you've described when reassembling and closing the mainspring, at least it is a very subtle spring back feeling when the hammer is fully in the forward position. I doubt the trigger's overtravel screw could be the issue, because once the bolt cycles the disconnector lever relieves the direct contact between the sear and trigger. The pistol's hammer functioning properly when the barrel is tilted upright is what caught my attention and led me toward the sear return spring.

How far did you tear-down this pistol frame. If you've detail stripped it perhaps looking at some my web help directions may be of some more help. http://www.guntalk-online.com/detailstrip.htm
(If the frame is a 22/45 platform than use these directions instead) http://www.guntalk-online.com/2245detailstripping.htm Each thumbnail photo can be enlarged by a mouse click to better see the details.

Let me know how everything matches up with the stripping procedures in your pistol so I can assist you further.

R,
Bullseye

 

[platapus]

Thank you Bullseye. I will attempt it again tonight when I get home with the link you gave. I really appreciate your help.