Check your magazine clearance in stock hole and make sure it's not touching. I think you said it was a threaded barrel if so I don't think you have barrel droop. As you stated make sure it has a champher.
Ten Ring

 

It's not threaded, its drilled and tapped for a scope mount. It is a little tight on one side of the magazine. It still clicks into place easily, and falls free when I push the mag release. If I sand the stock to get a litle more clearence, I will need to seal it to keep out moisture, correct?

 

Is it shaving little crescent shaped shavings? Mine does this too. I have been lurking and wondering how to fix this. I think I saw a post that said someone used a folded square of sandpaper to releive the barrel end slightly but I cannot find the post again..

Hub

 

I was the one that was having problems with the VQ extractor. Yours sounds a lot like what mine was doing. Do this is a safe place with the barrel pointed in a safe direction. Work the bolt slowly by hand and when it hangs stop. Look and see if the rim of the case is touching the extractor. If the extractor is too close it will not let the rim slide under it. If this is where the problem is, you can always remove the extractor and try the action again BY HAND. Don't try to fire the rifle with the extractor removed and only load one round in the magazine. If it works smoothly and doesn't hang up then then that would point to the extractor being the problem. If it still hangs then it could be the chamfer on the barrel, magazine postion, barrel mounting, etc. I did chamfer the barrel a little more on the bottom side before changing the extractor and it did help some. Also some lead in bullets are softer than others. Some bullets work great in my rifle while others will deform from being chambered.

 

I had the same problem w/ mine. I called GM directly and they told me that they let out some barrels with with not enough chamfering to the chamber and it looked as if I had one of those specific barrels. Less chamfering roughly equates to greater accuracy but at the expense of feeding/chambering issues. I took the barrel off, put it on a table, inserted a conical polishing/grinding stone into the chamber w/ my fingers and rolled the barrel back and forth on the tabletip until I reached the desired amount of 45 degree chamfer.

Let me state though that you probably only want to do this if you have exhausted all other options. You may want to call GM to see what they have to say as well.

shimbii

 

Well, I tried what gunther recommended. It seems as if the VQ extractor was the problem. I tried without an extractor and every bullet went in just fine. I also took out the bolt and tried to get a shell to go between the bolt face and the extractor, and it wouldn't without force. I put the factory extractor back in, and it seems to feed better now. I will really have to shoot it before I can decide if it worked or not. I am not real familiar with the work that CPC does on the bolt. I wonder if I had him do the bolt combo if it would help any with this problem. I am planning on doing it anyway sooner or later. Well, once I get a chance to shoot it again, I will give an update.

Thanks

 

I got to shoot it again this afternoon, and it is still shaving. The extractor was not the problem. I am changing back to the VQ because it worked better, and it will eject unfired rounds while the factory one won't. I am guessing that the problem is probably the stock being too tight aroung the magazine. If I was to sand the mag well, what could I use to seal it?

 

iceman,

Here's something to try with the gun pointed in a SAFE direction at a SAFE backstop. Chamber a dynapoint round under normal force and conditions and then exctract the round somehow and look to see if the lead is gouged w/ a crecent mark. After you do this, pull the action/barrel off the stock, reseat the mag on the stockless receiver and do the same thing again. Check to see if the round has the same gouge. If so, the stock is not the problem. I'm sure you get the point... just keep going with the process of elimination to find the cause. Also, is there a visible (but small) chamfer on the chamber mouth... maybe a millimeter or so at a 45 degree angle?

Did you do anything else to the gun at the same time that you put on the GM barrel?

The problem could be a bunch of different things:
-barrel/receiver alignment problem
-mag related problem
-mag/receiver alignment problem
-chamber mouth chamfer problem
-etc, etc....

hope this helps

shimbii

 

I don't think that it does it on every round. It seems like if it does it on one, it should do it on all of them, but I don't think that it does. I will try what you said though, about trying it with, without the stock.

Thanks

 

OK, I tore the rifle down again, and I looked at the barrel face, and I can't see any chamfer whatsoever. If there was no chamfer, could it still chamber? Is it possible for someone to show me a picture of what it should look like? I am gonna write GM, and see what they have to say.

Thanks

 

Is the GM barrel the only the only thing that you changed when the problem surfaced? is it still gouging w/ the stock off? Is your mag seating all of the way?

I had the same problem that you are describing right after I installed my GM barrel... and I also only stated to notice the issue when I started to use dynapoints. It seems like the dynapoints are a bit soft and have a shape that tends to hang up on the chamber mouth. After further investigation, I saw that all of my rounds, regardless of manufacturer, were getting gouged upon chambering, but only the dynapoints would fail to chamber all of the way. That's when I called GM and they informed by about the chamfer issues. I chamferred the chamber and the problem was solved.

shimbii

 

Well, the barrel was not the only thing that that I changed out. I ordered all of my upgrades at once. I changed the stock from the factory one to a Boyd's blaster, I put in a bolt buffer, I had a trigger rebuild by ttshooter, extended mag release, scope mount and scope. I tried it without the stock, and it still gouged the bullets like it did with it. I wrote GM, and am waiting a reply. I really appreciate the help. shimbii, just curious, where in AZ are you located?

 

so it sounds the stock isn't the culprit. I'd just make sure that you're mag is seating all of the way in. Just some more advice... it may make more sense for you to call GM instead of writing them. That way you can easily explain the problems and immediately answer any questions that they may have about your setup. Let us know how things turn out.

oh... I'm in the East valley as well. Too bad I didn't have more time to spending shooting.

shimbii

 

I got a reply from GM. They said that I can send it to them to have it chamfered, or I can do it myself. I really don't feel comfortable doing it myself, so I guess I'll have to send it back. This sucks, I'm gonna have do without my rifle for however long it takes them to get it right. Oh well, I gess its better than me screwing up a barrel trying to chamfer it.

 

iceman31

It's really not that hard i've had to do it on two of my barrels.You could probably get it done with scotch-brite and wouldn't have to send it back.You could give it a try and if you can't get it then send her back.:t

 

I have the same problem and have contemplated using a dremel with a conical grinding tip and GENTLY chamfering the entrance to the chamber. Is this a good idea, or too drastic?

 

chamfer

I have used a DeWalt drill driver instead of a diegrinder so as not to get to carried away.It doesn't take much to fix it.I have used scotchbrite on same type of attachment,just be carefull and it will work.

 

No power tools!!! Well, I guess you could if you were really carefull but I did it by hand and it came out perfectly.

Just get a dremel stone w/ a 90 degree conical tip. You can shape the stone to 90 degrees if needed by using a stone shaping/resurfacing block.

Now how to do it...

Place the barrel on a table top or other flat surface and roll the barrel back and forth with one hand while holding the stone in the chamber with the other. This method worked perfectly for me and is what GM recommended.

Hope it works out.

 

table top

Ok but be careful when you roll if it's fluted as you will mar the barrel.I have no problems with small hand tools as I machined and burred aircraft engine parts for Allison Gas Turbine,most of these parts were alot more expensive and precise than my barrels.It was an everyday occurence to put a radius or a chamfer on a $20,000 helicoptor engine part with a burrgun(diegrinder).I worked there 31 yrs. so I have plenty of experience:t
Actually you can just do it by hand without rolling and be fine as concentricity is not that big of an issue,All you need is a slight break in the dia.:t