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Posted: 1/19/2009 6:43:58 AM EDT
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I recently built a rifle from parts I had laying around. It is having some strange problems.
The bolt is well used and the barrel is almost brand new with less than 100 rounds through it. Check them with a field gauge and all is good. Brass looks fine also after firing. The problem is sometimes the the empty case will extract from the chamber but not eject from the bolt face and jam above the fresh round. Then the other day it would not eject the case from the chamber at all. Stuck case in a clean chamber, less than 30 rounds slow fired, three mags with 10 rounds in each. So I'm thinking weak ejector spring and maybe the extractor spring as well. Or can it be the extractor itself. Any advice on changing these since I have never had one of these fail before. |
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Possible.
You have checked for short stoking? What items have you completed from the list? http://www.ar15.com/forums/topic.html?b=3&f=66&t=210213 BSW |
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Instructions for bolt tear down starts on pg 2-39. Just make sure the spings dont go airborn or your never going to find them again.
http://www.ar15.com/content/manuals/TM9-1005-319-23.pdf You say its a well used bolt so exctractor/ejector isses are possible. However this could also be a symptom of short stroking. If it was me i would tear the bolt apart clean and lube it. If you have new springs throw them in. Take it back to the range. If the problem persists i would do the short stroke test. |
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Quoted:
Yes I can push it in with my nail. The extractor also moves easier than in my other rifles. How many foot pounds id you fingernail calibrated too? Do you have a new bolt to compare it to? It's hard to say for sure but it sounds like the ejector spring is toast. BSW |
| Not to insult your intelligence, but- is the barrel properly torqued to 30 " lbs, and did you check headspace? If so, trouble shoot the following: 1- is the weapon clean esp. the chamber, and then check for servicability of extractor. The copper spring with black pad and o-ring is usually the best bet. |
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Quoted:
Not to insult your intelligence, but- is the barrel properly torqued to 30 " lbs, and did you check headspace? If so, trouble shoot the following: 1- is the weapon clean esp. the chamber, and then check for servicability of extractor. The copper spring with black pad and o-ring is usually the best bet. No insult taken. Yes I checkd the torque on the barrel when installed. To be fair I have installed some barrels kind loose and a bit over tight to see how that affects them and have not noticed a difference in my 16" rifles. Headspace was checked with a sized case and a field gauge. I have not taken the extractor out, so don't know the condition/type installed. And I used a chamber brush on it after the first issue I had with it. I often find issues with lube and/or cleaning common problems. Strange that some of them you can toss in sandy water and they still work. I did use the spiral gas rings and have been told that those can cause these issues. They do make the bolt tight. |
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I also have this problem. The barrel and bolt are well used in mine. About ever 3rd shot empty casing jams above new round that gets stuck halfway into the breach. The ejector and spring are new. It takes some pretty good thumb force to push it in. The extractor is new as well as the spring. I also have used a d-fender ring which makes no difference. The gas tube and key are new and properly installed and tightened down. I installed the barrel to torque spec when i assembled it. It's lubed very well, and it will lock back on an empty magazine.
Could it be the headspace issue? I don't have a guage to test it but would that be an issue? The buffer is the original though the buffer spring is a new standard spring though. Any thought? Also i thought about buying a new barrel extension but i don't remember how to remove and install them. Also i thought about buying a new bolt to take up what i think is a worn amount of headspace to make the tolerance's tighter. The rifle is built in the 80's 
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Quoted:
Possible. You have checked for short stoking? What items have you completed from the list? http://www.ar15.com/forums/topic.html?b=3&f=66&t=210213 BSW Hey, that is cool, I've never seen it before. Now in my archive. Thanks cb |
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Quoted:
Quoted:
Possible. You have checked for short stoking? What items have you completed from the list? http://www.ar15.com/forums/topic.html?b=3&f=66&t=210213 BSW Hey, that is cool, I've never seen it before. Now in my archive. Thanks cb Some times I wonder about some of you guys, It is the first post in this forum, and is the check list for trouble shooting that should be read before even posting. 
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