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Chamber Scoring and Brass Imprints

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(@cahollandtruvista-net)
Member
Topic starter
 

Hi folks,

Would appreciate any feedback you can offer on the following. I purchased a custom build rifle from Impact Precision a few weeks ago. Pushed some cleaning patches through it, then borescoped before firing.

  • Impact 737R Action
  • Foundation MG2 in Dark Distressed
  • Hawkins DBM
  • Tac Sport Pro Trigger
  • 5mm Creedmoor, 24", M24 Contour, Graphite Black
  • Bartlein Impact by Stuteville barrel

Bore looked fine, but spotted some scoring in throat and chamber area and I’m not sure whether to be concerned or not. Fired 6 sight in rounds after scope mount. Some of the scoring was imprinting on my brass (fireforming new Lapua brass). At first I thought the imprint was from firing, but chambered a piece of new brass and ejected to find imprint on unfired brass.

Pics below show once fired brass with chamber marks that extend into shoulder. Also shows the most prominent chamber mark that extends in a straight line from shoulder body junction all the way to the bolt end of case. Imprints are light, but can be felt with fingertip or toothpick. The bottom case in one of the brass pics showing 3 short straight lines at body shoulder junction was caused by my opening and closing bolt 3 times. So if this repeats each time I reload and shoot, will these marks affect my case life?

Rifle seems to shoot fine, last two 1/8’ sight in adjustments at 70 yards with Golden Eagle were touching previous shot. So I may be concerned for nothing,  I’m just a bit disappointed with chamber scoring and looking for some feedback from some folks that have scoped other new chambers. Thanks in advance. This forum is much appreciated by me. Won’t hurt my feelings if you tell me to throw my borescope in the trash 😊.

Best regards,

Carl Holland







 
Posted : 01/29/2022 4:16 PM
(@william-schweers)
Estimable Member
 

 If this is a new rifle , I would contact them right away and send them the pictures requesting they replace that barrel .

The scoring is not good for your brass and judging by your pictures, too deep to polish out. Not to mention weakening the brass and rupturing.

 
Posted : 01/29/2022 6:29 PM
(@richard-naber)
Member
 

Carl, 

Is your magazine a metal one? One thing I have experienced in the past that I thought was happening in the chamber, were a long scratch the length of the brass on 2 sides of the brass. It turned out to be caused by the feed lips on the magazine. If that is what is causing the scoring, you can lightly smooth the feed lips with a fine grit sandpaper! Make a mark at the 12 o’clock position of the brass with a sharpie, load it into the magazine keeping the mark at 12 o’clock then feed the round or just the brass case into the chamber. Slowly eject it out of the rifle and check the brass to see if the scoring marks are roughly at the 3 and 9 o’clock positions on your brass. If so it is probably caused by the magazine feed lips. Good luck!

                             Rick

 
Posted : 01/29/2022 6:54 PM
(@gqhoon)
Member
 

Not normal and not acceptable. Contact the supplier and give them the opportunity to put it right.

In any manufacturing / production process, QC oversights do occur. A reputable supplier would want the opportunity to correct this sort of issue.

 
Posted : 01/29/2022 7:52 PM
Russell Dee reacted
(@cahollandtruvista-net)
Member
Topic starter
 

Thank you: William, Richard, and Rick for your replies.

Rick. All 6 of the rounds and the new piece of brass were hand fed and I will definitely take your advice on smoothing the feed lips. Thanks.

William - Richard. This is a new rifle and the brass in the pics is the 1st six rounds fired by me. I was glad to hear your advice since that was the way I was leaning. Hopefully Impact Precision and Stuteville will be good folks to deal with. I'll let you know what happens..

 

 
Posted : 01/29/2022 9:26 PM
(@smallgroups)
Famed Member Admin
 
Posted by: @cahollandtruvista-net

Hopefully Impact Precision and Stuteville will be good folks to deal with. I'll let you know what happens..

 

You'll have no issues with them.  

 

 
Posted : 02/01/2022 1:04 PM
(@cahollandtruvista-net)
Member
Topic starter
 

Thanks Eric,

 

I sent an email message to Tate @ Impact at 11am Sunday, not expecting or needing a reply until the first of the week. Received an email from Wade Stuteville 2 hours later requesting that I send the barrel directly to him. Can't get more responsive than that !

Here is a portion of Wade's response "I do want to note that the marks described as :  The bottom case in one of the brass pics showing 3 short straight lines} are caused by the case rubbing against the inside of the receiver during extraction due to side pressure from the spring loaded ejector.  These will be on any case extracted from the receiver and are not caused by the chamber."

I am curious to see if you or any of the members have experienced this and if there is an adjustment of some sort to prevent the marks on the brass.

 

Best regards,

Carl Holland

 

 
Posted : 02/01/2022 2:09 PM
(@aufdej25)
Member
 

with regards to the 3 straight scratches. I've seen that before. With your bore cam see if there are anymore threads exposed on the inside of your action that aren't being taken up by the barrel. That's what I usually see the cases make contact with during extraction prior to ejection. 

 
Posted : 02/06/2022 3:05 AM
 Carl Holland
(@Carl Holland)
New Member
 

Wade Stuteville has my barrel and receiver right now so can't look, but I believe you are right on with your diagnosis. Here is an excerpt from an email Stuteville sent me a few days ago.

"I removed it from your action, inspected it, and installed it on my function test action.  It has the extractor installed but no ejector.  This allowed me to extract cases without the ejector pushing them up against the inside of the receiver and scratching them.  I dropped 5 cases in the chamber and extracted them.  No scratches were present.  I then fired the 5 cases and no scratches were present.  All of the scratches on your brass are being caused by feeding from the magazine, being fed into the chamber mouth, or extraction with the ejector pushing the case against the inside of the receiver as I had mentioned prior to you sending the barreled receiver. "

I hand fed all 6 of the rounds in the pictures, so assuming mine are caused by the ejector pushing the case against the side of the receiver. Do you consider this normal? Do any of your bolt actions rifles mark the brass in this manner and do you think if will affect the case life?

Your response was much appreciated.

Best regards

Carl Holland

 
Posted : 02/06/2022 1:26 PM
(@smallgroups)
Famed Member Admin
 

Mag's can be terrible on brass.  It's very possible.  

 
Posted : 02/07/2022 11:27 AM
(@richard-naber)
Member
 

I believe I mentioned that to you Carl!

 
Posted : 02/07/2022 9:32 PM
 Carl Holland
(@Carl Holland)
New Member
 

Rick,

 

Yes you did and I've been working on smoothing my mag feed lips today as a matter of fact. Thanks for the tip.

Carl

 
Posted : 02/07/2022 11:10 PM
(@richard-naber)
Member
 

You are most welcome Carl, I only know this because I experienced it with a new rifle too, luckily I figured it out! I was very happy to know that it was not the rifles fault! 
                       Rick

 
Posted : 02/08/2022 2:08 PM
(@rustywonder)
Member
 

@richard-naber Something along those lines, With my Savage 110 Elite precision I have noticed brass shavings in the area between the end of the barrel and bolt. I get this whether I am hand feed or mag feed. I am suspecting that the extractor may be shaving a bit off the lip when the bolt is closed, opened or both.

Curious if anyone else has seen this?

I have removed the extractor and polished the edges to see if that corrects the issue. I am also thinking of putting in a weaker ejector pin spring.

 
Posted : 06/02/2022 3:58 PM

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