Harder bolt close after sizing

[Chiquita]

I would do a few things. Measure the diameter of the .200 line on another piece of brass that closes just fine and compare it to a piece that has just been fired, and then to a piece that has just been resized. Do you see a difference in that dimension?

Do you have access to a Teslong borescope? You can insert it from the chamber side to see if you have a carbon ring that has gradually built up, or anything else impeding the chamber. You can insert it from the crown end with a closed bolt (to include an empty case, not a live round) to see if your necks are too long.

I do have a bore scope and I will do as you suggested.

 

[Bc'z]

I do have a bore scope and I will do as you suggested.

Try measuring the body shoulder junction

 

[Chiquita]

Pay particular attention to the neck and shoulder junction and the shoulder to body.

About the only way to increase diameter of the case while sizing would be to crush the shoulder, possibly from too soft after annealing. This would show up at the body to shoulder area.

If the sizing ball is pulling the neck forward on the way out, it would mark at the base of the neck. Sizing a problem case without the expander would prove this as the problem, if it fits after sizing.

The key is a fired case fits before you anneal and size.

What happens to a fired case that you do not anneal before you resize?.

Annealed case fits fine. I noticed when I sized it then it was a hard bolt close. Again, I don't remember having this issue in the past.

 

[jelenko]

Hmmm. Sounds like something is loose or moving.

 

[dellet]

Annealed case fits fine. I noticed when I sized it then it was a hard bolt close. Again, I don't remember having this issue in the past.

Sorry wasn’t clear with my question.

What happens if you size a case that has not been annealed?

 

[Ccrider]

I have seen case get longer moving the shoulder forward during sizing. The black marker will tell you where contact is being made.

It is pretty simple. The case is either too long, too long at the shoulder or too big at the 200 line.

If everything is fine after firing with no bolt click, my bet is that it is the shoulder and you need to bump it back more.

 

[drop_point]

What type of die? Is it possible the die lock ring has had the threads stretched out with use? I agree with the black sharpie trick, I've used it myself a time or two.

 

[Chiquita]

Sorry wasn’t clear with my question.

What happens if you size a case that has not been annealed?

Same, harder bolt close.

 

[Chiquita]

One more thing that I noticed the cases measure smaller this morning since they were left out in the shop over night. Does colder environment affect the test material and the test equipment?

 

[Chiquita]

What type of die? Is it possible the die lock ring has had the threads stretched out with use? I agree with the black sharpie trick, I've used it myself a time or two.

Redding full size die.

 

[Chiquita]

With small base die. Still harder to close.

 

[Big_Daddy]

Try measuring the body shoulder junction

THIS^^^^^

 

[JMayo]

If you have a bore scope, put in a case close the bolt. Scope from muzzel and see where case mouth is.
My 30br was too long. I even got a ring die thinking .200 line ...

If no bore scope trim case that is tough to close on and see if it gets better.

 

[Chiquita]

If you have a bore scope, put in a case close the bolt. Scope from muzzel and see where case mouth is.
My 30br was too long. I even got a ring die thinking .200 line ...

If no bore scope trim case that is tough to close on and see if it gets better.

Distance between the edge of the brass and the end of the chamber with the bolt closed. I have plenty of room.

 

[Chiquita]

So with the Redding you are sizing :
.0015 at the .200 line
.004 at the CSJ - (excessive )
.002 length -bump ( increase here)


Small base die:
.0015 at the .200
.005 at the CSJ- (excessive )
.002 length -bump

Just my 2 cents

.004 and .005 "excessive" you mean the case shrank too much or not enough?

 

[243winxb]

with .004 shell holder

Put away the Redding competition shell holders. Use a standard shell holder. Normal shell holder has a deck height of .125"

 

[Chiquita]

Put away the Redding competition shell holders. Use a standard shell holder. Normal shell holder has a deck height of .125"

How does the competition shell holder screw things up and make the harder bolt close?

 

[dellet]

I don’t load 308, so I’m a bit confused with the numbers and the drawing.

View attachment 1314321

Your “C” measurement is being referred to as “base to Datum” in your first post. This is base to shoulder. Base to datum would be measured as drawn, close to the center of the shoulder at a spot that is .400” diameter and should be somewhere around 1.630”. Note the drawing below.

How are you getting your measurement?
Are you using a different diameter tool than .400” to get your 1.57+ number?
Are you just measuring to the shoulder with calipers?

As I said I’m not familiar with the 308 cartridge but your numbers don’t make sense to me.

If you are not measuring to the actual datum, it would all make sense. The shoulder will move forward and lengthen, before the die contacts the shoulder and pushes it back. This would cause your problem and using the standard shell holder would likely correct it.

But we need that length number at the .400” diameter of the shoulder to know for sure.

 

[47WillysGuy]

	His	Mine	Saami
A	0.453	0.453	0.455
B	0.470	0.470	0.470
C	1.5685	1.615	1.634 -0.007

I compared OP numbers to the SAAMi drawing and my .308 numbers and His "C" which is a headspace number is almost 0.065 of an inch different from Sami and 0.046 of an inch from my readings. I used the Hornady "D" insert to get the 1.615" my headspace dimension.

Saami's dimension from case head to body/shoulder junction is 1.5598, OP's dimension of His "C" is 1.5685 which gives a difference of almost 0.009 of an inch difference.

As dellet says, "But we need that length number at the .400” diameter of the shoulder to know for sure."

The 1.5685" dimension is suspect to me... What tools/method are you using to get the 1.5685" number?

 

[JMayo]

Here is another couple of thoughts ...

Sholder angle of die not matching chamber.

Calipers not reading correctly.

Method in which measurements are being taken.

Lol you've got from A to Z being thrown at you. Good luck. Let us know when you find that needle in that haystack !