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Discussion Starter · #1 ·
Seems to be rubbing on the top of the receiver while cycling... Take a look. The extractor is being worn in a way that I have not seen before - What say the experts? Should I stock up on extractors? Big deal? No?

Tilt test is smooth as butter.

It's my pre ban so I really, really don't want to send it to SAI.

FYI I have a spent case holding the bolt out of battery for the photo.




Thanks!
 

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Do not be afraid, just act like you got a bucket full of them to work with.

I would start with a small round file, like for small chainsaws, and place it in the inside concave, where the turn is, and smooth it up filing one direction only, from the front to back, then take a small triangular file and finish off the flat to match where you can see it is worn, just taking enough to stop it from hitting the barrel shroud, then work the humpback right side from the bottom at the curve and up and over the rise, using rolling action with the file, then sandpaper to smooth file marks, then reblue with cold blue and oil it.

Watch for more wear and re-file as needed till it stops rubbing.

Or, if you are really good with it, use a dremel tool to knock it down, but be advised, a dremel will take a lot of meat quickly with a heavy hand.
 

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Whats the receiver look like where its making contact?
 

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Don't forget to check the bottom of the extractor on the bottom side of the bolt and see if the extractor is sticking out too far. You can file off a little on the bottom of the extractor's shaft/pin? what ever you want to call it. That would give a little more clearance on the top side of the extractor. Also, I don't know if a weak spring would cause the extractor to move around in such a way as to cause that kind of contact but replacing the spring wouldn't be expensive.
 

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Don't forget to check the bottom of the extractor on the bottom side of the bolt and see if the extractor is sticking out too far. You can file off a little on the bottom of the extractor's shaft/pin? what ever you want to call it. That would give a little more clearance on the top side of the extractor. Also, I don't know if a weak spring would cause the extractor to move around in such a way as to cause that kind of contact but replacing the spring wouldn't be expensive.
Excellent post Rammac....shame on me for forgetting to mention cause and effect, or permanent fix....hence the old saying, "two heads are better than one".
 

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Discussion Starter · #6 ·
Thanks for the replies guys! I don't believe it is hitting the barrel shroud as it's got plenty of clearance there. I believe it is contacting the rear upper part of the receiver as it gets to the rear most part of the cycle.

Here's some more pics. I looked at the underside of the bolt to see if the pin is protruding but it is not - it feels pretty flush to the bolt.






 

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Yep, It looks like you got yourself a poorly cast upper terminal on the receiver bridge area. The 60 degree arc bolt pass through even shows to be wavy in that area from your pic.

Have you changed out stocks on this rifle in the past or is it original stock ?

How is your trigger group lock-up, tight or loose ?

I was thinking maybe the hammer and the bolt riding up on it throws it too high into the top if you changed the stock.

Does the bridge area show excessive wear at that location ?

If not, looks like you may need to return to SAI to have bridge upper addressed.

One thing that puzzles me, is the first pic of the ones you just posted, shows some mushrooming on the extractor down in the concave inside 90 degree turn,...this usually indicates barrel shround contact or receiver forward contact.
 

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Discussion Starter · #8 ·
Yep, It looks like you got yourself a poorly cast upper terminal on the receiver bridge area. The 60 degree arc bolt pass through even shows to be wavy in that area from your pic.

Have you changed out stocks on this rifle in the past or is it original stock ?

How is your trigger group lock-up, tight or loose ?

I was thinking maybe the hammer and the bolt riding up on it throws it too high into the top if you changed the stock.

Does the bridge area show excessive wear at that location ?

If not, looks like you may need to return to SAI to have bridge upper addressed.
I have changed the stock - This stock definately has a tighter lockup than the commercial stock that came with the rifle.

For grins I pulled the charging handle back and looked through the selector switch cutout. Upon drawing the bolt back, it does make significant contact pushing the hammer down. I changed stocks to one with a looser lockup and it does provide a bit less contact.

The bridge area does not show any wear to speak of.
 

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Discussion Starter · #9 ·
One thing that puzzles me, is the first pic of the ones you just posted, shows some mushrooming on the extractor down in the concave inside 90 degree turn,...this usually indicates barrel shround contact or receiver forward contact.
Here is a shot of the bolt just before it drops into battery. I have a spent case seated in the bolt. I figured this would push the extractor outward a bit and exaggerate any issue in the shroud area. It looks to me like there's plenty of room there, but I'm not sure.

Thanks again

 

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Ok, look at the barrel at approximately 1:30 where the overhanging lip of it ends, and look for damage there, post upside down pic of area if you can. Probably getting contact as it comes out of battery on recoil there. Watch as you rotate it back out of battery, and look for contact, then multiply that action at 50,000 cup pressure for when a round goes off.
 

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Discussion Starter · #11 ·
I've tried every which way to get that extractor to come close to the barrel cut out and I just don't see how it could make contact there. It's just not close.

I took a macro shot of the barrel at the cutout from underneath:




By the way I really appreciate you helping me out here. This site is fantastic. FRG1
 

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No problem, I live for this stuff !!

Ok, couple more checks and we can narrow it down to the top of the receiver being where its hitting.

As it comes out of battery there is plenty clearance, this clearance is maintained partly by the bolt roller being captured by the op rod. The op rod has a degree of flex from up and down, and twisting motion left and right. Check your bolt roller with it out of the op rod and see if it is loose, extremely loose, like a broken clip inside the roller.

With the rifle assembled and operating it slow, and coming out of battery, flex hard on the op rod handle up and to the left and see if it gives enough room to crowd closer to barrel shroud. While doing this with your right hand, and at the same time, push down on the left side of your bolt, with your left thumb, see if it hits then. Remember ,when fired, this is much more violent, and if the gap is very small with you doing it by hand, it could be hitting when fired.

If it doesn't and the roller is good, then your contact is on the upper part of the receiver. You might could work it down some yourself, but it might void warranty, probably best left to SAI.
 

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Seems to be rubbing on the top of the receiver while cycling... Take a look. The extractor is being worn in a way that I have not seen before - What say the experts? Should I stock up on extractors? Big deal? No?

Tilt test is smooth as butter.

It's my pre ban so I really, really don't want to send it to SAI.

FYI I have a spent case holding the bolt out of battery for the photo.




Thanks!
I've had the same wear mark on my Loaded 1996 model. I've corrected it as per ripsaw's post # 2. Take off just enough on the extractor to give the needed clearance. dozier
 

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Discussion Starter · #14 ·
No problem, I live for this stuff !!

Ok, couple more checks and we can narrow it down to the top of the receiver being where its hitting.

As it comes out of battery there is plenty clearance, this clearance is maintained partly by the bolt roller being captured by the op rod. The op rod has a degree of flex from up and down, and twisting motion left and right. Check your bolt roller with it out of the op rod and see if it is loose, extremely loose, like a broken clip inside the roller.

With the rifle assembled and operating it slow, and coming out of battery, flex hard on the op rod handle up and to the left and see if it gives enough room to crowd closer to barrel shroud. While doing this with your right hand, and at the same time, push down on the left side of your bolt, with your left thumb, see if it hits then. Remember ,when fired, this is much more violent, and if the gap is very small with you doing it by hand, it could be hitting when fired.

If it doesn't and the roller is good, then your contact is on the upper part of the receiver. You might could work it down some yourself, but it might void warranty, probably best left to SAI.
Roller is good, bolt will absolutely not hit the barrel no matter how I contort the op-rod.

I think I will keep shooting as is and monitor the wear. I may re-blue the worn spot on the extractor and see if it continues. I do not shoot this rifle often, so I don't think I'll wear it out anytime soon!

Thanks again for the help. I'll update down the road.
 

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Sounds good Andy, it might have already worn in, all it's going to. The blue is a good idea to tell for sure. Keep us posted if you have any more trouble.
 

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My Springfield has the wear mark as well. No issues whatsoever so I'm not concerned.
 

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ahhh...

It's like a freckle on a girlfriend, it's adds personality. lol

seriously, I'll have to check both of mine, as they are still in the breaking-in stage.
 

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My SAI did the same thing with one extractor. I replaced the extractor and the problem went away.

The replacement was USGI. I do not know the origin of the problematic one.
 
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