Rifle Chamber Questions

Oh man I can understand your frustration. That would have me torqued. I would normally think dies with that type of issue but it's on the fired cases and not just one but consistent. If it was the brass you would see it before firing. I understand what your describing in the case neck. I did not do a good job on my end describing it. Let's see what happens with sizing once you put it in the rock chucker as that will eliminate anything screwy there. One thing, if you still have virgin brass start with it inntge rock chucker so we are not seeing rements from already buggered cases.

By chance, did you neck turn the cases after you opened the neck up from .30 to .338?

I can not see how you using too much lube during sizing is causing this as its showing after firing not sizing. I assume you are cleaning the cases after sizing so dry chamber and case, no lube in chamber.

I hope going to the rock chucker is going to clear up the 0.006 needed shoulder set back as that just should not be happening.

Hey if there is still an issue after trying the RC press I could send you my die for a week or so to try to rule out something weird with the die.

Just be sure to try at least one virgin case to see once you change over.

I want to think on this for a bit. I will post back. Issues like this get under my skin to figure out.
 
By chance, did you neck turn the cases after you opened the neck up from .30 to .338?
I haven't, but that's been in the back of my mind, and I might try it just to see if that changes anything at all.
A different die is something I should have done already, just to eliminate that possibility.
 
You could have another gunsmith do a mold cast of the chamber. That will tell you the story how well it was reamed and give you evidence if done incorrect.
The gs that chambered it cast it, said it was good. I have what I need to do it myself, and I should probably do it, but haven't yet.
 
Do you have a bore scope to check out the chamber? If so, maybe take some pics of the chamber and post those as well. If you don't have one, I would suggest Amazon and Teslong Scope they are very cheap and pretty good for the price point.
 
Ripples on the cartridge almost sounds like "chatter" in the chamber. Maybe a dull cutter, lack of enough coolant and it got hot when reaming, bad pilot, something.
But removing the cartridge and putting it back in and it won't chamber might require you to index mark the the cartridge and see if it will fit back in the way it came out with index mark lining up.
It's one way to verify or eliminate that possibility.
A re-chamber with a new sharp reamer may correct the errors if your chamber is that rough.
 
I can't see too well from the picture but it looks like the reamer may have chattered. This isn't too uncommon and although I have no proof, I think it occurs mostly when the guy doing the chambering is trying to take another thou or 2 to hit a particular headspace number if that makes sense. A borescope will tell the tale.

Looks like Bob and I were typing at the same time :)
 
I got a other idea. If you know someone with a lathe, and if you have the ability to remove the barrel, then chuck the barrel in the lathe and indicate off the bore that hasn't been cut, right in front of the leade to center up the bore. Then you can measure the concentricity of the chamber to see if you can detect the waviness that you suspect.
 
Do you have a bore scope to check out the chamber? If so, maybe take some pics of the chamber and post those as well. If you don't have one, I would suggest Amazon and Teslong Scope they are very cheap and pretty good for the price point.
I have a borescope and have looked at it. I really can't see anything that seems of concern, but I don't know what I'm looking at either
 
Ripples on the cartridge almost sounds like "chatter" in the chamber. Maybe a dull cutter, lack of enough coolant and it got hot when reaming, bad pilot, something.
But removing the cartridge and putting it back in and it won't chamber might require you to index mark the the cartridge and see if it will fit back in the way it came out with index mark lining up.
It's one way to verify or eliminate that possibility.
A re-chamber with a new sharp reamer may correct the errors if your chamber is that rough.
I will clock rounds next time I shoot it and try that
 
I can't see too well from the picture but it looks like the reamer may have chattered. This isn't too uncommon and although I have no proof, I think it occurs mostly when the guy doing the chambering is trying to take another thou or 2 to hit a particular headspace number if that makes sense. A borescope will tell the tale.

Looks like Bob and I were typing at the same time :)
This is exactly what I think has happened, but haven't heard if it's even possible. I have heard that a reamer can't cut anything other than a perfectly round hole, but I'm really not too sure if that is necessarily always true. Theorizing I wondered if he was bumping the lathe at the end to get where he wanted to be and inducing little ridges around it. Not sure exactly how it can happen, but my necks don't come out of the chamber exactly round
 

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