Ruger Mark II - Failure to feed problem

[creitzel]

Hello all,

I'm having a problem with my new Ruger Mark II. Every once in a while, it fails to feed a round, and the round will get caught by the bolt as it closes, causing the gun to jam up. I at first thought that this might be due to the cheap remington thunderbolt ammo I was using. I have since tried a few different kinds of ammunition, and am starting to believe that ammo has nothing to do with it.

I have noticed a pattern to it, in that whenever it happens, it is on the 8th or 9th round in the magazine. In other words, it will fire the first 7 or 8 rounds from the magazine fine, then jam up. Could this be a problem with one of my magazines ( I have 2 )? Maybe one of them doesn't have an adequate spring in it? I was going to try to disassemble the magazines when I cleaned it today, but apparently you need some sort of special tool to do this. The manual says

With right hand, insert drift punch in hole and depress Magazine Block Retaining Plunger approximately 1/4".

but I've never heard of a drift punch(I'm not the most mechanically inclined lol).

The only thing I can think to do now, is to mark one of the magazines, so I can see if it is a particular one of them that is causing this every time. I'm going to put a little dab of my wife's finger nail polish on one of them before I take it to the range tomorrow.

Any help you guys can give me in regards to this would be greatly appreciated.

Thanks in advance,

Chris

 

[Jim K]

A drift punch is simply a straight, round cylinder, usually with a larger portion to use as a handle and place to pound on with a hammer. You can use anything similar, like a plain nail, to do that job, though I suggest you file the point off the nail.

Jim

 

[creitzel]

Jim,

Thank you very much for the information. I'll see if I can dig something up in the garage to do the trick.

Thanks again,

Chris

 

[Chuck Dye]

I played "shoot to failure" with my MkII and several bulk pack ammo varieties. I reached the same conclusion as I think you may reach: keep it clean (including magazines) and stop buying Remington bulk pack ammo.

BTW, it would be helpful if you would describe exactly what kind of failure: failure to extract; failure to eject (ejector failure or incomplete bolt travel failure); failure to feed-no cartridge pickup, nose diving, or stovepiped new round.

 

[creitzel]

I played "shoot to failure" with my MkII and several bulk pack ammo varieties. I reached the same conclusion as I think you may reach: keep it clean (including magazines) and stop buying Remington bulk pack ammo.

Yeah, I quit using the thunderbolts, thinking they were the problem (I also didn't like the extreme amount of fouling they did to my bore, but that's another issue). But today, the gun jammed 5 times, using a combination of 2 different types of CCI ( mini-mags and stingers ) ammo, and some winchester as well ( x22lr ). Keeping it clean is definitely not an issue, as this is my first gun, and I'm babying it more than I do my kids lol.

BTW, it would be helpful if you would describe exactly what kind of failure: failure to extract; failure to eject (ejector failure or incomplete bolt travel failure); failure to feed-no cartridge pickup, nose diving, or stovepiped new round.

The problem I'm having is a stovepiped new round. It seems like the round is being "stood up" in the chamber, then the returning bolt is stove piping it. This is why I was wondering if it might be a magazine problem. As I stated before, it always happens on the 8th or 9th round out of 10.

Thanks,

Chris

 

[pete f]

try this too. go buy one new mag in the wrapper and mark it so you know which is new. go to gun range and try the same test. You may find that the failure to feeds go away. Also with the old mag, try lightly lubind the bolt and seeing if the problem goes away. Do only one fix at a time. that is, oil it see if that works if it does then that is the issue. If not, then try the new mag, you may find that the old one has a bent feed lip or some such damage that prevents the last rounds from sittting the proper orientation when the slide operates. As the # of rounds decreases in the Mag, the inertia of the stack to hold the round in perfect position is decreased, thus increasing the importance of perfect feed lips.

 

[Chuck Dye]

If I understand your description correctly, the bolt comes to rest against the side of the case with the bullet pointing roughly 90 degrees to the bore axis. I suspect the rims of the offending rounds are not being shoved into the clutches of the extractors as they clear the feed lips of the magazine. This keeps rim so low relative to the bore as it moves forward that the nose is able to ride over the mouth of the chamber, producing the failure to feed. With a full magazine, the spring is compressed enough to overcome whatever is wrong.

The magazine spring may be failing to spread normal extractors, due to an out of spec spring (short or weak), out of spec follower (short or binding), or an out of spec magazine tube (binding).

You may have normal magazines that are unable to lift the rim into the extractors . that may be due to fouling of the extractor springs, though shooting to failure with my MkII produced failures to extract. Disassembly of the extractors is not difficult. I have used plastic dental picks with some difficulty, trying to compress the pins without scratching anything, and jewelers’ screwdrivers with ease without scratching anything. I like the K-Mart screwdriver sets for about $4 and have several scattered through house, cars, and gun kits. I strongly recommend removing the extractors while holding the bolt in a box deep enough to corral flying springs and pins.

If the extractor springs and drive pin channels are clean and nothing is binding, the last possibility I see is that one or both extractors were miscut by Ruger and must be replaced.

My own experience with Ruger is very positive: Ruger has replaced broken extractors and firing pins on my MkII and some friends’ MkIIs and 10/22s without hesitation and without allowing us to pay for the parts or even the shipping. I would not hesitate to call them.

Edit to add: BTW, several of the Rugers we have repaired with free parts were in the hands of the fourth or fifth owners. I like Ruger service!

 

[creitzel]

pete

Thanks for the suggestion. I'm getting ready to go to the range today, and I just oiled both of the magazine springs. We'll see if it makes a difference or not.

One of the magazines seems to have a rough spot when moving the button to compress the spring. This rough spot seems to correspond with where the spring would be around the 8th or 9th round. I have marked this magazine with a little of my wife's fingernail polish, so if it is the one failing, I will know it. The rough spot decreased after oiling the springs, so maybe oiling will fix it. I'll post again after my range trip today.

Thanks again,

Chris

Edited to add: I'm also going to see if the gun shop at the range has any magazines for the Mark II. If so, I'll pick one up, and see if that eliminates the problem.

 

[creitzel]

Huck

If I understand your description correctly...

That is exactly what is happening. I am going to try oiling the magazine springs today, per pete's suggestion, and see if that fixes the issue. As I noted to pete, I can feel a rough spot when compressing the spring by hand on one of the magazines. Maybe this is the cause?

As for the rest of your post about the extractors, please forgive me, but I'm fairly new to shooting, and this is my first gun. I don't know what the extractors are, or what they look like. So far, I've only disassembled the gun per the owner's manual, which is basically taking the main-spring assembly out, removing the bolt, and the barrel receiver assembly. I assume, from your description, that the extractor is one of the little parts that are part of the bolt assembly? I apologize for my ignorance. I'm definitely willing to learn, if you're willing to expend the energy on me

Thanks,

Chris

 

[Chuck Dye]

The extractors are clearly marked in the exploded diagram Ruger prints in the owner’s manual. At the 9 o’clock and 3 o’clock positions of the bolt face, they have the appearance of crab claws held in front of a crabs face. As the bolt moves forward from its full recoil stop, the bottom of the bolt strikes the top of the next cartridge in the magazine and drives it towards the chamber. As the cartridge clears the feed lips of the magazine, the magazine spring drives the freed cartridge up between the extractors. On all of the MkIIs I have observed, the extractors are spread apart as the rim is seated on the bolt face. The extractors are tensioned by spring and pin pressure more easily seen in the diagram than described here. If the extractors are requiring more seating force than the magazine spring provides (the nature of springs is that the force provided by the nearly empty magazine is notably less than that provided by a full magazine) it could be due to one or more of the causes I described. The rough spot you describe seems a likely culprit.

If you don’t have the Ruger owner’s manual, Ruger will provide one free of charge, or you can download one at http://www.ruger.com/Firearms/S-InstructManualsP.html

 

[HankC]

this may help, it cured my 22/45:

http://www.1bad69.com/ruger/stovepipe.htm

 

[creitzel]

Huck

Thanks for the clarification. I've been concentrating on the disassembly pictures in the manual so much, that I totally missed the exploded picture at the back of it. Now I can see what the extractor is. I've never taken it off of the bolt when I disassemble the gun. On a side note, my gun only appears to have one extractor, at the nine-o-clock position on the bolt face.

Anyways, my wife and I went to the range today, and she put about 250 rounds through the Mark II ( I was playing with a rented Glock 19 ), with no failure to feeds at all. I think oiling the magazines helped. I still don't know what is causing the rough spot, but once I oiled it, the rough spot was decreased substantially. I think I'm going to take that magazine apart, and see if maybe there's some kind of small obstruction or something in there. Worst case scenario, I'll just pick up another magazine.

Thanks a bunch for all your help.

Hank,

Thanks for the link, I'm adding it to my favorites in case I need it later


Chris

 

[johnnytang24]

I don't know the problem, but if you're looking to buy mags, you can order the parts from Ruger and assemble the mags yourself for less than half the price. I think if you call, they have a list of parts cause so many people do it. Also, you can use a paper clip as a punch to disassemble the mags.

Thanks.

 

[wally]

if you're looking to buy mags, you can order the parts from Ruger and assemble the mags yourself for less than half the price. I think if you call, they have a list of parts cause so many people do it. Also, you can use a paper clip as a punch to disassemble the mags.

Last time I ordered parts from Ruger, they didn't send any of the mag parts saying they were "out of stock" and the parts prices were going up This was in Feburary if I remember correctly.

I'd like to be wrong....

--wally.

 

[Chuck Dye]

Ooops! Sorry, you have me there-the MkII does have only one extractor (been dealing with a 77/22 which has two.) What I have described still applies.

From my shoot to failure fun, I have acquired the habit of flushing the MkIIs spring and plunger pit occasionally with Hoppe's when I clean the gun, but as I have said, fouling there caused failures to extract. The syringe I use came from Brownells and is sold singley by many gun shops if you don't want the sixpack.

 

[rock jock]

I had the same problem, tried several solutions, none of which worked. Sent it back to Ruger and they fixed it. Something to consider.