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Posted: 8/8/2004 7:01:38 PM EST
Put a 7.62x39 upper together myself a while back. Colt 7.62 upper, DPMS complete bolt, Bushmaster assembled bolt carrier. Put one round of Wolf in a USGI 5.56 20-round mag, loads and fires fine, bolt locks open, but the spent shell sits in the upper receiver right above the mag. Is it a bad extractor on the bolt?
Link Posted: 8/9/2004 1:40:58 AM EST
First thing I would try is a strronger extractor spring. Get a couple of the Wolff HD extractor springs www.gunsprings.com.


If you still have problems, try different brands of ammo, and see if any of them work. I know the US made stuff is often not as potent as some of the Russian made ammo
Link Posted: 8/9/2004 3:58:43 AM EST
By the way, I'm using the new polymer-coated Wolf. I remember read somewhere that it's underpowered. Does that have something to do with the ejection problem?
Link Posted: 8/10/2004 8:55:53 AM EST
[Last Edit: 8/10/2004 8:56:55 AM EST by HK_DUDE]
I would say ejector....the extractor is doing it's job if it takes the empty out of the chamber.....the ejector isn't pushing the case head hard enough to pop it off the bolt at the rearward position.

Maybe?..........I could just be smokin' again
Link Posted: 8/10/2004 3:37:23 PM EST

Originally Posted By HK_DUDE:
I would say ejector....the extractor is doing it's job if it takes the empty out of the chamber.....the ejector isn't pushing the case head hard enough to pop it off the bolt at the rearward position.

Maybe?..........I could just be smokin' again




You just might be The vast majority of failures to eject in ARs are caused by a weak EXTRACTOR spring. The case starts coming off the extractor on the way back out of the chamber, so the ejector can't get enough of a push on it to pop it out of the reciever.

This topic has been discussed numerous times on the site, over the years. I will say though that given ar15seeker has only used one type of ammo, he might want to try another brand before he does anything else. In any event, the HD extractor spring is chaep, and I have them on all 5 of my ARs. For what little they cost, it's cheap insurance
Link Posted: 8/10/2004 8:01:18 PM EST
I agree cheap ammo, especially that (more varnish than my dinning room table) stuff. Look around the site there are tons of people with the same problem. I know it is cheap, so you can shoot tons of it. But how much fun is it to clear misfeeds and rounds stuck in the barrel.
And we all know how much you spent on a 7.62 ar. Why put crap through it.
Link Posted: 8/11/2004 6:37:54 AM EST
I'll try some Winchester. If that doesn't help, I’ll try a Wolff extractor spring.
Now I think about it, the end of my 7.62 extractor does not have a little piece sticking out to click into the groove on the rim of the shell like my 5.56 extractor. Is that the way it suppose to be? Other 7.62 upper owners please comment. Maybe I’ll post a picture when I get home. Thanks.
Link Posted: 8/11/2004 12:22:09 PM EST

The case starts coming off the extractor on the way back out of the chamber, so the ejector can't get enough of a push on it to pop it out of the reciever.



That makes sense....if it's not getting a good hold of it, it lets go.

Link Posted: 8/12/2004 4:32:54 PM EST
I have 4 ARs in 7.62x39. My first one is a colt sporter which functioned flawlessly out of the box. I have built each of the others. Each of the builds required some tuning to get reliable operation. I have had the luxury of swaping parts with the colt to identify problems. The first kit I assembled was a oly which included an assembled and "test fired upper." It failed to extract, left the case in the chamber. The problem was it had a 5.56 extractor which would not grip the 7.62 case. Changed the extractor and solved the problem.

In respsonse to your question on the extractor, it should appear identical to a 5.56 extractor. The only difference is in the radius and width of the grove in the extractor which grips the rim of the case. I have seen a 7.62 extractor that the grove was ground off center, deeper on one edge and very shallow on the other. This casued a failure to extract also.

I'd try removing the bolt and fitting a round or case into the bolt. the extractor should firmly grip the rim of the case. If you tug on the case while keeping it line with the axis of the bolt, it should be difficult to seperate the case from the bolt. You can also get a feel for the force of the ejector by rocking the case towards the extractor. I have resorted to assembling the bolt carrier without the firing pin and cycling rounds with the charging handel after I have made a change to the bolt asembluy to test function.

As to the wolf ammo. Is is all I run through my 7.62 ARs. After 6-7000 rounds the only ammo related problem I have encountered was failures to fire as the result of inadequate firing pin protrusion. Seems the primers on the Wolf 7.62 are harder than on the Wolf 5.56. Removed .015" from the tail of the bolt and have since run 1500-2000 rounds without any further problems.

The only magazines I have found which are 100% relaible are the "frankenmags"

It's been and adventure but the 3 that I built are as reliable as teh factory colt.

Good Luck

Link Posted: 8/22/2004 2:22:38 PM EST
I bought (stole for 50 bucks) a yugo sks with an empty stuck in the chamber and a couple of boxes of wolf ammo. Thing was FULL of cosmoline. A swift stike of the butt on the floor cleared the jam. A good cleaning made it better, but it wouldn't run. it'd stovepipe or rechamber the empty. Today I bought some remington ammo and it worked as designed. Wolf must have had a run of bad ammo.
Link Posted: 8/28/2004 6:28:58 PM EST
Thanks all for all the great inputs. DPMS will replace my broken extractor for free.
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