Brass scraping chamber walls

[RyeGuy]

Anyone know why brass is doing this? 6.5 Saum, ADG new and FL sized.. Tried double checking jam and shoulder bump measurements with sizing fired brass, pulling ejector and sizing in small increments until bolt falls and rises with ease. Well my chamber is not letting my brass move freely. I’ve marked up some brass to see where it’s hitting, the fired brass hits in 2 spots, new brass hits in 1.
(w/ Whidden or Redding dies)
Any advice to move forward is appreciated. Or do I just shoot it and not worry about it? It doesn’t take a lot to close bolt but it starts hitting about 1/2” from lug engagement. So after a couple firings it will probably fill like pressure issues and/or clickers?? Or is this a GS issue which needs chamber cleaned up. Pics of fired brass, 2 spots.

 

[RyeGuy]

New brass, only the 1 spot hitting.

 

[Straightshooter1]

Anyone know why brass is doing this? 6.5 Saum, ADG new and FL sized.. Tried double checking jam and shoulder bump measurements with sizing fired brass, pulling ejector and sizing in small increments until bolt falls and rises with ease. Well my chamber is not letting my brass move freely. I’ve marked up some brass to see where it’s hitting, the fired brass hits in 2 spots, new brass hits in 1.
(w/ Whidden or Redding dies)
Any advice to move forward is appreciated. Or do I just shoot it and not worry about it? It doesn’t take a lot to close bolt but it starts hitting about 1/2” from lug engagement. So after a couple firings it will probably fill like pressure issues and/or clickers?? Or is this a GS issue which needs chamber cleaned up. Pics of fired brass, 2 spots.

When sizing your brass, do you give any dwell time, leaving the brass fully in the sizing die for a few seconds (like 4 or 5 seconds)? If not, you might try that and see what you get.

 

[rwj]

Can you post a picture of the chamber wall? If the scratches are occurring during chambering, it would seem that there must be some burrs present and/or a very rough finish.

 

[Straightshooter1]

Can you post a picture of the chamber wall? If the scratches are occurring during chambering, it would seem that there must be some burrs present and/or a very rough finish.

Good point. I had this burr issue for a factory barrel that was leaving scrapes up at the shoulder-body junction. Had the factory replace the barrel.

 

[RyeGuy]

I will try dwell time longer, (I usually do 1-2sec) And yeah I will try and get pics of chamber walls with borescope tonight
Thanks for advice

 

[Coyotefurharvester]

Did you reset the seating die(body) after the first firing, before seating bullets in the fired brass?

 

[RyeGuy]

It’s definitely not reamed correct. My sizer size the brass to .549, virgin is .545, fired is .550. And it’s that spot that hits, right at the back of the chamber. Hard to tell in the pics. But in the middle of “the hump” there is a small chunk missing. When looking with naked eye I can damn near see the imperfection of the diameter.
#4 is the black from the marker. #5 is the edge, looked pretty rough so wanted to see other’s opinion. Also to noticed a chunk of metal missing from action.

 

[Rsadams]

Try cleaning the chamber with a brush vigorously , then reinspect.... I hope most of that is carbon or lead or moly... Is the brass resized properly...

 

[RyeGuy]

This pieces missing from action is pretty close inline with the bad spot in chamber. Anyone have an idea what would have happened? You don’t ream with action on do you? If so maybe it clipped action? I don’t think that effects anything just caught my eye since I was looking so close. $6000 for this rifle

 

[RyeGuy]

Try cleaning the chamber with a brush vigorously , then reinspect.... I hope most of that is carbon or lead or moly... Is the brass resized properly...

I’ve tried. There shouldn’t be any carbon, lead, moly towards the back of the case?

 

[Rsadams]

I’ve tried. There shouldn’t be any carbon, lead, moly towards the back of the case?

How long has it been since a chamber scrubbing...???? Where I would start at...

 

[rwj]

I believe you have sufficient information to seek an explanation, and remedy, from either the smith or prior owner.

 

[BigBolt]

I had some brass scarfing on cases when I had a M77 Rugar in 30-06 and after inspection I found some micro burs in the chamber. What I did was to polish the chamber using a wooden dowel that I made to fit the chamber. I glued some crocus cloth around the dowel and used some polishing compound too. after twisting the dowel by hand, the chamber was completely polished like a mirror. I never had any other cases show up with scarfing.

 

[Webster]

This pieces missing from action is pretty close inline with the bad spot in chamber. Anyone have an idea what would have happened? You don’t ream with action on do you? If so maybe it clipped action? I don’t think that effects anything just caught my eye since I was looking so close. $6000 for this rifle

Not an expert at bore scope interpretation. Looks like cotton patch fibers attached to burrs in the chamber. Is it a factory barrel. Did you have an amatuer gunsmith chamber the barrel? Cannot image what caused that big gouge mark. A light polishing the chamber may help.

 

[Webster]

I will try dwell time longer, (I usually do 1-2sec) And yeah I will try and get pics of chamber walls with borescope tonight
Thanks for advice

I never could find an engineering write up on hold time in a die for brass. A lot of data for springback of Al in dies. With Al it takes at least 2 minutes hold time to even measure a tiny change. Been reloading since 1970 never had any kind of problem. Maybe I'm lucky.

 

[Coyotefurharvester]

The measurements .550-.545 are those at the 0.200 line on the case. If you were able to measure @ .200 the fired and sized .549 would be ok for a Saum chamber. Although one firing and 0.005 growth seems like a pressure issue? Repeatable measurement @ the 0.200 line is tough, most calipers are +,- 0.001. Polishing the chamber should be possible with your measurement numbers and sizing die.

 

[jelenko]

I never could find an engineering write up on hold time in a die for brass. A lot of data for springback of Al in dies. With Al it takes at least 2 minutes hold time to even measure a tiny change. Been reloading since 1970 never had any kind of problem. Maybe I'm lucky.

With 223, I've tried holding , but found no measurable difference

 

[6.5 forever]

With 223, I've tried holding , but found no measurable difference

The same with my 6.5 CM Lapua.

 

[mikecr]

How much runout in the sized cases?