Over pressure?

[Pete1979]

Over pressure?

Sometimes a small base die isn't enough. I've posted before on older threads about a lot of Lake City OFB I got years ago. Two of my presses would not bump the shoulder. Had to run them through the Forester with Imperial sizing wax to get the job done. I've had the same problem with other mil-surp 7.62 like CAVIM and IK. I've also had a few well used cases where the necks thickened and hardened to the point that the shoulder pulled forward on the up stroke, you could hear a squeak on the way out of the die and into the trash can...

Some of that surplus is really tough stuff.

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[LynnJr]

J-Cat has it right the cases are most likely swelled in the web area just in front of the case head.
Tight closing is usually a shoulder bump and a click on opening is usually a tight web area. And both can be easily fixed by proper sizing.
That said if you neck size only you will eventually have to bump the shoulder.

[fguffey]

As for the OP . I did not read all of the second page of this thread but I get a sticky bolt at minimum charge and FL sizing once and awhile . I figured it out to be that I bump my shoulders back .002 from fire formed case . Some times you can get press deflection and or spring back and the shoulder does not get set back . In this case when fired the case reacts more like a neck sized only case . As we all know Neck sizing only can produce sticky bolts even though you are not over pressure . I thought of this after looking at the pics . The case shoulder seem to be making hard contact with the chambers shoulder . That would indicate his CASE head space is to long for the chamber . Just a thought

Start over. a reloader should be able to measure the length of the case from the shoulder/datum to the head of the case. Repeat, does anyone on this forum know how to measure the diameter of a case body? after that, Is there anyone on this forum know how to make gages that could be used to measure the diameter of the case body?

Measuring the length of the case before chambering, measure the length of the case after firing and again after returning the case to minimum length/full length sized.

the Wilson case gage is a case gage, it is not a head space gage. My cases do not have head space, my chambers have head space.

Some times you can get press deflection and or spring back and the shoulder does not get set back

Metal God, What you are saying you can not determine if the press sized the case when the ram was raised? A good reloader can determine if the case won or the press won before lowering the ram. The case can build up resistance to sizing. There are times the lube is not sufficient. there are presses that do not have the ability to overcome the cases resistance to sizing.

Some times you can get press deflection and or spring back and the shoulder does not get set back

I find it most difficult to set the shoulder back without case body support meaning when I size the case and shorten it from the shoulder to the case head everything gets set back because I am full length sizing the case back to minimum length. When my press deflects I can measure the amount of deflection in thousandths.

F. Guffey

[Metal God]

I find it most difficult to set the shoulder back without case body support meaning when I size the case and shorten it from the shoulder to the case head everything gets set back because I am full length sizing the case back to minimum length. When my press deflects I can measure the amount of deflection in thousandths.

The feeler gage is a nice tool to have

Metal God, What you are saying you can not determine if the press sized the case when the ram was raised? A good reloader can determine if the case won or the press won before lowering the ram. The case can build up resistance to sizing. There are times the lube is not sufficient. there are presses that do not have the ability to overcome the cases resistance to sizing.

Yep , and you played a roll in helping me understand that . The feeler gage is still a very good tool to have at the bench . I however went with competition shell holders to remove all press deflection .

Before I bought the comp shell holders . If I was getting deflection or spring back I would shim the case up between the case and shell holder

[LynnJr]

As you can see members become dysfunctional when someone disagrees with them, I would agree with you if he had said what you claim he said.

He started in a manner rather rude, I do not have many ways to tell someone they are mistaken. The case does not have a base and a case head.

I agree, the case has a web. Then the question about measuring the length of the case from the shoulder to the case head and the diameter of the case body.

ar15barrels was the only response, and then he was responded to in a manner rude rather. responding in a socially dysfunctional manner should not be accepted.

F. Guffey

Frank
I think J-Cat has a good grasp of what is taking place here.
I think AR15 Barrels has a good grasp of what is happening here.
I think J-Cat and AR15Barrels rarely disagree with how things work. We have a picture of the cases shoulder but we don't have a picture of the web area of that same case with magic marker on it.
To answer some of your direct questions most don't measure the datum point because it is of no use to most reloaders. As you have mentioned it requires special gages that fit the taper of a case and it doesn't help ones reloads at all.
My reloads have set 4 world records and won a National Championship and I never measured nor do I know any benchrest competitor who measures the datum point.
On forums such as these we run across many ways to skin a cat.
I am kind of open minded so I tried your method out using the feeler gauges.
While it works it isn't the way I would go.
I use my rifles chamber to determine when and how much shoulder bump to use as SAAMI spec on belted magnums varies about 0.025 inches.
If I was to use your methodology I would need so many gauges I couldn't afford to shoot. All my assets would be tied up in gauges and it wouldn't help accuracy.