Gunsmithing Possible burr in chamber

[Shifty6BR]

Hey guys, I just had a barrel spun up in 6 dasher, using Norma brass, did some load development and after doing some more brass work I noticed some cuts on my brass towards the shoulder area. Im not one to get too hung up on things so I just figured to continue and let her break in.

Well yesterday I had one particular piece of brass that I had chambered a few times to check the setup of my body/bump die. So naturally everytime I chamber checked that piece it was putting cuts into it, all around the body towards the shoulder junction. Fired that round off and she was stuck...I mean stuck, I had to beat the bolt open with a rubber mallet. The other pieces of brass I fired which had just one cut not multiple in them extracted fine, and rechambered fine.
Measurements on the shoulder length on these brass were in line as I had resized all the brass I was firing that day. Neck length was also in line.

I chambered some virgin brass and sure enough there was a cut in the brass so I think I can rule out a die issue. I feed my rounds via single shot loading block so I think I can also eliminate a mag lip issue/feeding hangup as the issue as well. Bore was cleaned prior to range day.

Fully intend on getting in touch with the builder this week...kinda sucks waiting this whole time only to send it back, but hell I guess time I have a lot of.

Heres a pic any feedback would be greatly appreciated, thanks all.

 

[Milo 2.5]

I'd bet it's not in your chamber. Something sharp is on the side of the action and the marks come from extraction. Chamber a loaded rd and eject it, see if it is present.
Pics always help.

 

[DAVETOOLEY]

Very common. When the case clears the chamber the ejector pivots the case over to the front corner for the bolt lugs. Remedy. Next time the barrel is off polish that corner.

 

[FatBoy]

happens on my AI and my Tempest. The corners of the breach ring are sharp and scratch the brass. Has zero impact on my brass performing. I wouldn't assume the scratches are causing the cases to get stuck. Do you have any other pressure signs?

 

[Shifty6BR]

Thanks for the input guys!! Ok just got back from an early morning range run...the weather here is disgusting today.

I cooked off that particular piece of brass today at my chosen powder charge, she went off fine and chambered right back in fine. So as stated before, the issue with that particular piece may of been a matter of something else. I did do a lazy mans fireform with this norma brass before working up to full house loads and did push a few pieces into the red zone after, definite pressure signs but not to the point of really hard bolt lift but...maybe perhaps it may of been instigated somewhere in that time frame as far as pushing this Norma brass too hard. My tuned loads are showing no pressure issues and looks like I can get a few firings before bumping the shoulder and body back.

The cuts in the brass I can give zero f's about I was just wondering if it can have an adverse affect on chambering but as of today's test and the general consensus it does not seem that way and I'll take yesterday's event as an anomaly.

Thanks again dooders.

 

[Rebelirons]

Both of my Badger M2013's do this. That asshole breech ring

 

[ZiaHunter]

The neck on Norma Dasher Brass is long vs Lapua 6mm BR brass which is the parent case for most Dasher's. To be on the safe side check your neck length.