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Posted: 9/22/2015 5:53:52 PM EDT
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I've just completed my qc10 glock lower build.
Qc10 glock lower 4.5" 40sw barrel Gibbz side charger upper Sd3g trigger Jp 9mm sc spring Qc10 bolt Octane 45 silencer About 1 out of every 10 shots will stove pipe. I'm also having about one out of every ten fail to reset trigger but I will fix that with a little weld. I just have no idea why the stove pipe. Thanks |
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What Mad Machinist said....
The ejector on this design has only a TINY space on the head of the case to actually do its job. If the ejector isn't perfectly aligned, it won't eject the empty case, so the fresh round will push the empty off the bolt face and either shove the empty up and forward, or outward a bit and look like a "stovepipe" jam on a .45. The fix is easy, but it's important to not screw around with the ejector if that's not the issue. Pictures, please!!! |
| Yes, failure to eject. I have a hard time posting pics on here but I can't see anything wrong with ejector. I have tried different buffers and different buffer spring on silent capture spring. I don't see how the trigger could have anything to do with the failure to eject. Thanks for the help |
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try bending the mag spring right under the follower to place more pressure on the rear of the follower.......if you can take a pic of the ejector form the side....some have a slight downward angle on the nose that can cause your issue....but I haven't encountered it on a QC10 lower. If you hold a round in the pocket of the bolt under the extractor will the round fall out if you turn the bolt 90 degrees from verticle. Bolt pocket diameter on 4S&W is still somewhat uncharted territory......I have had a snug bolt pocket cause the malfunctions you describe in a 40 as well. You also might try pulling the extractor and filing just a small amount off the face......where it would meet the bottom of the extraction groove on the round......or just bending it back a little........I haven't played with a QC10 bolt yet.......so I can't say for sure....but I think most of your problem ie between the mag and extractor......do you have a caliper and can you measure form the side of the firing pin hole to the side of the extractor hole?
Rudy |
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Quoted:
<a href="http://s1048.photobucket.com/user/junkyone/media/image.jpg2_1.jpg.html" target="_blank">http://i1048.photobucket.com/albums/s361/junkyone/image.jpg2_1.jpg</a> <a href="http://s1048.photobucket.com/user/junkyone/media/image.jpg1_1.jpg.html" target="_blank">http://i1048.photobucket.com/albums/s361/junkyone/image.jpg1_1.jpg</a> The second picture shows your ejector bent quite far OUTWARD. It needs to ride inside the ejector channel in the bolt REALLY CLOSE to rubbing on the bolt. I'll bet that's your problem right there. |
| GH....that is a QC10....it actually has a floating ejector.......no bending it......99% sure it is the round hanging in the bolt either due to a tight pocket....or the extractor is hanging on too tight to the rim.....either bending it back a little or dressing a little off the nose should solve the ejection issue. |
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The last picture shows a spent round on the bolt face under the extractor. I can shake it like a ketchup bottle and the case won't fall out. I'm not sure if this should be like this or not?
I haven't got back in touch with qc10 yet but I did ask if the ejector should have that much play in it. They said it probably was fine but send pics. Thanks for all the help. This little project is a little bit of a pain but fun. |
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I would say the bolt is your problem....drive out the roll pin that holds the extractor in.....remove extractor and see if the tip has a slight bend in it.....if so try and straighten it...be careful it only takes a little....if not try grinding/filing just a little off the tip of the extractor at the point where it ....before you do this....put a round in the bolt pocket with out the extractor...it should fall out.....you should have at least .005 to .008 clearance between the case rim and the side of the bolt pocket.....if it is too tight....let me know and I'll try and help you out....
I have 7 or 8 QC10 lowers......really not sure how many.....  and the floating ejector is perfectly normal.....a loaded round falls out of my personal 40 S&W bolt......
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| Remove your trigger and put a standard trigger in and try that also you may need to get a different spring from jp for your scs. The bolt is probably dragging on your trigger and your scs is also probably too tight so you're not letting the bolt get enough speed and back far enough to eject a round properly. Just try it and see if it works. |
| First off this am I pulled extractor and filed around edges to make it smooth and checked bolt face with shell to make sure I had clearance. When I putextractor back in the round was not nearly as tight as before a shell would fall out if shook. I also put the second lightest jp spring in scs. I had same issues when test firing but not quite as often. I then put in a mil spec trigger and test fired. I had no fails to eject but I did have a couple fails to feed. I figured I needed more spring so I put the heaviest jp spring in. I shot a full 22 round mag and had one fail to eject and three fails to feed. By fail to feed I mean that the new round is sticking out of barrel by a 1/4 to a 1/2". I think I'm going to get some different ammo and clean and oil gun. |
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Not so much rounding as actually shortening the hook.....just a little......010 or so......what you want is to prevent the extractor from pushing the case rim into the wall of the bolt pocket opposite the extractor...this can slow down the action of the ejector flipping the spent case out......also hand cycle a round .......slowly extract till you see it hitting the face of the ejector.......look to see where it is headed......is it centered on the port or a little low?
Your buffer and bolt velocity could also be an issue.....no experience with JP springs and buffer........but as it is for a 9mm it could be too light causing excessive bolt velocity.......I know I run a heavier buffer in a 40 than I do a 9............ |
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Quoted:
GH....that is a QC10....it actually has a floating ejector.......no bending it......99% sure it is the round hanging in the bolt either due to a tight pocket....or the extractor is hanging on too tight to the rim.....either bending it back a little or dressing a little off the nose should solve the ejection issue. It still looks like that ejector is way too far out to work properly. My QC10 lower's ejector is WAY closer to midline that shown in that picture... |
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