Shoulder bump problem or no problem?

[Tidesloe]

I've got a new blade micrometer coming this week, and I'll remeasure everything carefully before firing on all cases, and after firing more loads this weekend. My measurement have been with a relatively inexpensive, probably 15-20 yr old calipers. Time to upgrade some measuring instruments. Might make a difference. We will see

 

[Tidesloe]

The chamber dimension at the .200 datum is .555" and all of his sized cases measure .553" or less. How could it be the web?

If you would, measure a few fired brass when you fire more, and let me know what your chamber measures.

 

[Tidesloe]

Tidesloe: What am I seeing in the red circle above? Do you have the ability to cut a die in half across its circumference?

That's extractor mark, I believe

 

[ChrisInKY]

That's extractor mark, I believe

Just a blemish ... or is it a gouge? On every case ... or just the one?

Pretty sure your answer is already lurking in this thread. Still watching for an outcome. Brass sure can tell us a lot!! My lead guesses at this point would be

• your sizing die is slightly larger than what you need for your specific chamber
  • Dilemma: is it the die that's wrong or the chamber?
  • Won't know if it's not measured accurately (up, down and all around)
• could be an ID donut (remember: another fella using the words (paraphrasing), "almost imperceptible")
  • I might have missed it: did you measure at each step of the process? And, I'm talking even before you fire formed?
  • I can tell you're not looking for some run-of-the-mill plinking cartridge. If you really want to eliminate potentials from the equation, you're going to have to section your 'sacrifice' cases lengthwise and actually look.

I found this just now: https://forum.accurateshooter.com/threads/no-small-base-die-for-338-lapua-workaround.4031019/
Same ideas. Really interesting responses. Going to have to go back and read the whole thing now.

 

[Tidesloe]

Just a blemish ... or is it a gouge?

Blemish on every one

Pretty sure your answer is already lurking in this thread.

That I'm sure of. Just don't know which yet.

 

[Tidesloe]

It's got to be one or the other. I just can't see anything else.

 

[Barehandlineman11]

The blemish is on the rim though from your ejecter. If it was the issue you couldn't get it to go away. Still needs fixed there too

 

[Tidesloe]

That is responding to chamber or die problem. Do you or anyone else here know how I can measure my chamber ID accurately. The fact that I've got to size the web area down to .551 to chamber without resistance seems to be a concern to me. The chamber should be .555

 

[Tidesloe]

The blemish is on the rim though from your ejecter. If it was the issue you couldn't get it to go away. Still needs fixed there too

Ok that's possible also. I did say earlier that the ejector pushes the case slightly off center of the bolt face. Possibly this could be the issue? Ejector making too hard contact? That would be best case scenario, if so

 

[Barehandlineman11]

That's about correct. I size my lapua and normas .004 to not get clickers. They cycle smooth with less. Id really question if chamber is .555. Or its not concentric good possibility. I messaged you with die i found.

 

[Tidesloe]

That's about correct. I size my lapua and normas .004 to not get clickers. They cycle smooth with less. Id really question if chamber is .555. Or its not concentric good possibility. I messaged you with die i found.

That's what I question also. Several possibilities here. If the chamber isn't concentric that's an unfixable problem

 

[Shane Lindsey]

Regardless of what the readings are telling you, it still chambers with too much resistence. So if it is .553 or .555 or .551. When it doesn't chamber with resistance it is probably being set back too much to have any consistency let alone brass life.

Mine goes from very hard to chamber to very loose and you can see a ring around the neck shoulder junction that looks like a dimple. My bet is the Hornady dies...

 

[Tidesloe]

Regardless of what the readings are telling you, it still chambers with too much resistence. So if it is .553 or .555 or .551. When it doesn't chamber with resistance it is probably being set back too much to have any consistency let alone brass life.

Mine goes from very hard to chamber to very loose and you can see a ring around the neck shoulder junction that looks like a dimple. My bet is the Hornady dies...

I saw a reamer print this morning, and there should be plenty of clearance, even on what I measured on fired cases. Rich told me that the Hornady dies are too tight. I need to measure my chamber ID, and my die ID. A good bit of searching comes up with nothing on measuring chamber ID. If those measurements are good, seems like I'd have to think about an in concentric chamber? Maybe brass length? These are the things I can most easily verify for now, but come up with nothing on how to measure chamber ID. Any piece stands a possibility that it could have gone out, out of spec. It shouldn't happen, but always a possibility

 

[ChrisInKY]

Do you or anyone else here know how I can measure my chamber ID accurately.

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Measure your die too.

This is the pain you've brought onto yourself, Brother. But you will come out better on the other side.