• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Harder bolt close after sizing

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.
 
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.
 
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?
 
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.
 
Screen Shot 2022-02-05 at 3.10.19 PM.png

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?
 
With small base die. Still harder to close.
 

Attachments

  • 20220205_152712.jpg
    20220205_152712.jpg
    529.8 KB · Views: 20
View attachment 1314321

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?
With small base die. Still harder to close.
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
 
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.
 
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.
Screen Shot 2022-02-05 at 6.59.12 PM.png

Distance between the edge of the brass and the end of the chamber with the bolt closed. I have plenty of room.
 
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?
 
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?
 
I don’t load 308, so I’m a bit confused with the numbers and the drawing.
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.
527D999F-9100-4284-8279-FC6D72565628.png
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.
 
Last edited:

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
166,230
Messages
2,213,892
Members
79,448
Latest member
tornado-technologies
Back
Top