MKIII mag position jams?

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Georgezilla
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MKIII mag position jams?

Post by Georgezilla » Fri Oct 28, 2011 5:36 pm

Ruger recently replaced my defective MKIII with a new MKIII, the new pistol has 450 rounds through it. I have been experiencing many jams that look similar to a stove pipe, except the case usually stays in line with the cartridge that is being fed (i.e. the spent case is lined up right above the cartridge that is being fed). I have expereinced about 20 of these jams in 450 rounds.

My ejector does not touch the rear mag feed lips, and the feed lips do not knock the spent case off before the ejector does, but there is only ~1/64" clearance between the rear mag feed lips and the ejector. I have checked the mag release button and it is fine, no flash or anything, and I do not want to modify all my mags as I want to purchase another ruger .22 auto pistol down the road. I think that the ejector is so high that too much of its force is directed upward instead of outward when the jam occurs.

My question is do you think what I have described is indeed caused my the mag being positioned too high? Does the pistol perhaps need more rounds through it before a conclusion should be made?

If you think I do have an issue, is Ruger likely to fix it? If I send it in, is Ruger just going to fire 30 rounds, and if they do not have one of these malfunctions just disregard all of my research/measuring, or do they usually replace the frame quickly with mag positioning issues.

Any input is appreciated, thanks.

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Post by Bullseye » Fri Oct 28, 2011 5:45 pm

This sounds more like an extractor that is not tensioning the spent casing tight enough. It could be the mag is positioned a little too close to the ejector or even that the LCI is dislodging the spent case prior to it striking the ejector. The easiest thing to try is removing the LCI and see how the pistol functions. If the spent cases are ejecting normally then the ejector is not tensioning them tight enough to the breech face. A new VQ exact edge extractor claw may be just what the pistol needs for smooth functioning.

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Georgezilla
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Post by Georgezilla » Fri Oct 28, 2011 5:51 pm

Sorry, I should have mentioned that the pistol does have a VQ exact edge extractor in it. I have checked via manually operating the bolt with a spent case and the LCI does not appear to dislodge the case. Also the VQ extractor seems to be holding the case pretty good, however, I do not really know what enough tension is.

I will remove the LCI as you suggest, and clean the pistol and see if the issue persists. Thanks for the advice.

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Post by Bullseye » Fri Oct 28, 2011 5:54 pm

Enough tension is sufficient force to hold the case on the extractor hook to the ejector pin. You should be able to set a loaded case on the bolt and mildly shake it without the round coming off of the extractor. Remember a live round is heavier than a spent case, so this is a good test of an extractors hold ability.

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Post by Georgezilla » Fri Oct 28, 2011 6:05 pm

I placed a loaded case on the bolt and I was able to shake it very hard and without the round coming out. The bolt does allow the round a bit of vertical play though. When the round is on the bolt under the extractor tension you can wiggle the round up and down, not sure if that's normal.

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Post by blue68f100 » Sat Oct 29, 2011 9:12 am

To check the LCI, push on it with a punch. If does not instantly fallow you (spring back) it's gummed up and needs cleaning. A good test is to remove it like Bullseye suggested. I keep all oils and solvents away from it when cleaning the receiver area. All they do is wash junk into it and gums it up quicker. I'm able to go around 2500 rounds between detail cleaning.

Another thing to check is to make sure the mag is not running too high and knocking the spent round off before it hits the ejector.
David

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Post by Bullseye » Sat Oct 29, 2011 1:38 pm

George it sounds like your extractor is tensioned correctly. A loaded round is significantly heavier than a spent casing. That just tells me that the spring and plunger are not gummed up with shipping preservative - you did clean out all that preservative right? A little bit of movement is all right for the casing as long as it stays on the hook. Checking the LCI is the next step.

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Post by Georgezilla » Sat Oct 29, 2011 4:45 pm

Thanks for the advice Blue and Bullseye.

Blue, the LCI seems to function smoothly when I actuate it with the punch.

Bullseye, I did detail stripped and cleaned out all the preservative prior to firing it. I will remove the LCI and give it another cleaning just to ensure i get all the metal filings out from the break in process. Hopefully I will get a chance to do these 2 things tonight so I can try the pistol again tomorrow.

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Post by Georgezilla » Sun Oct 30, 2011 6:25 pm

I ran 350 rounds through it today without the LCI and fresh after a detail clean, experienced one jam that was in a different configuration then the previous ones (pictured below). 1 out of 350 is a significantly better ratio then the pistol had been experiencing. I presume that removing the LCI made the difference, but I wish I had not cleaned it so I'd know for sure.

This is the configuration of the one jam it experienced without the LCI:

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Post by blue68f100 » Sun Oct 30, 2011 9:11 pm

Looks like a stove pipe to me, with one in the chamber.

You can reinstall the LCI to see if was the main cause.

Check to see if the magazine is setting too high. If it is, it will knock the spent case off before it hits the ejector.
David

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