Faulkner
Member
After a session at the range I was field stripping my MKII. I have a duly issued Man Card so field stripping a Ruger MK pistol isn't an issue for me. This time, though, I had something new happen that I've never encountered before. As I was holding the gun sideways and pulled the bolt out of the receiver I noticed a pin fell out onto the cleaning mat. Hmmm, were'd that come from?!? As I continued with my cleaning I kept searching for an empty hole in the frame where this pin could have come from. When I picked up the bolt and gave it a once over, I noticed a hole in the side of the bolt that seemed to be the right size and the pin slide right in. I've field stripped MKII's, MKIII's, and MKIV's untold numbers of times and I've never had this pin slip out of one before.
Although the pin obviously came from that hole, there was no tension holding it in so I did some internet investigating on the subject and learned that the firing pin rebound spring is what holds tension on that pin. The spring is under the firing pin in the bolt, so I removed the firing pin, then turned the bolt over and the spring came out in two pieces . . . not good.
I learned that the pistol will work without this spring and detent pin, but this is the part that keeps the firing pin from hitting the face of the bolt. With this in place, you can safely dry fire any Ruger MK pistol without fear of damage, but with a broken or missing spring and detent pin you can damage the firing pin and bolt face when dry firing. The evidence that you have a broken spring is that the retaining pin will fall out when you pull the bolt out, like mine did.
I then went back on-line and downloaded an exploded diagram and found the part number. The next morning I called Ruger's customer service line and in short order was on the phone with a nice lady who asked what kind of problem I was having. After a brief explanation she asked for my serial number and when I gave it to her she said, "wow, looks like that's a MKII stainless that's about 35 years old."
"Yes ma'am," I replied, "my wife bought it for me as a college graduation present"
"Okay, so you're the original owner" she asked.
"Yes, does that make a difference?"
She said, "no, just found it interesting that you've had it all this time."
"Yep, I've put a zillion rounds through this pistol", I said. "I've got several more but this one is my favorite. Never had a problem with it before now."
She asked me if I had an account number and I said I did, I still had my number from when I had to send my MKIV in for the warranty recall. I gave her the number and she confirmed my name and contact/mailing information. She asked if she could put me on hold for a minute and would get right back to me. Less than a minute later she came back on the phone and said, "I've got you a replacement spring in a little bag along with a new rebound spring holder. We'll put it in the mail and you should get it in about 3 to 4 days free of charge."
Sure enough, the package showed up in the mail 3 days later and that evening I installed the new spring and spring holder, which was simple enough. Took it out for a test firing and it's as good as new.
Thank you Ruger for the excellent customer service experience.
** The moral of the story is, for you guys who say you never field strip your Ruger MK pistol and just spray and wipe it down, by not field stripping it you could be missing the possibility that your detent spring is worn or broken and you expose your pistol to dry fire damage. My recommendation is to go apply for a Man Card and then learn how to field strip your Ruger MK pistol. I'm telling you, it ain't that hard.

Although the pin obviously came from that hole, there was no tension holding it in so I did some internet investigating on the subject and learned that the firing pin rebound spring is what holds tension on that pin. The spring is under the firing pin in the bolt, so I removed the firing pin, then turned the bolt over and the spring came out in two pieces . . . not good.
I learned that the pistol will work without this spring and detent pin, but this is the part that keeps the firing pin from hitting the face of the bolt. With this in place, you can safely dry fire any Ruger MK pistol without fear of damage, but with a broken or missing spring and detent pin you can damage the firing pin and bolt face when dry firing. The evidence that you have a broken spring is that the retaining pin will fall out when you pull the bolt out, like mine did.

I then went back on-line and downloaded an exploded diagram and found the part number. The next morning I called Ruger's customer service line and in short order was on the phone with a nice lady who asked what kind of problem I was having. After a brief explanation she asked for my serial number and when I gave it to her she said, "wow, looks like that's a MKII stainless that's about 35 years old."
"Yes ma'am," I replied, "my wife bought it for me as a college graduation present"
"Okay, so you're the original owner" she asked.
"Yes, does that make a difference?"
She said, "no, just found it interesting that you've had it all this time."
"Yep, I've put a zillion rounds through this pistol", I said. "I've got several more but this one is my favorite. Never had a problem with it before now."
She asked me if I had an account number and I said I did, I still had my number from when I had to send my MKIV in for the warranty recall. I gave her the number and she confirmed my name and contact/mailing information. She asked if she could put me on hold for a minute and would get right back to me. Less than a minute later she came back on the phone and said, "I've got you a replacement spring in a little bag along with a new rebound spring holder. We'll put it in the mail and you should get it in about 3 to 4 days free of charge."
Sure enough, the package showed up in the mail 3 days later and that evening I installed the new spring and spring holder, which was simple enough. Took it out for a test firing and it's as good as new.
Thank you Ruger for the excellent customer service experience.
** The moral of the story is, for you guys who say you never field strip your Ruger MK pistol and just spray and wipe it down, by not field stripping it you could be missing the possibility that your detent spring is worn or broken and you expose your pistol to dry fire damage. My recommendation is to go apply for a Man Card and then learn how to field strip your Ruger MK pistol. I'm telling you, it ain't that hard.
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