Please Help Me Solve a Mystery

oneskilledshooter

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I am doing some load development for a 30-06 Remington 700. I was just going to try out a Lee collett neck sizing die and I noticed that I cannot slip a bullett in to the necks of my twice fired Winchester brass. This is BEFORE I have done any kind of prep to the brass except tumbling. I called Lee today for some help with the neck sizing die (completely unrelated questions) and I asked their tech support and they were puzzled. I only have 60 cases and it is not possible that they have been mixed up or anything. These cases were from factory Winchester ammunition, fired, prepped, full length sized, reloaded, crimped with the Lee factory crimp die (very lightly, the lightest reccomended setting). Then I fired them all and tumbled them.

Any ideas? I would expect the neck/mouth to be loose enough as to allow a bullet to be pushed in the the case with no resistence :confused:
 
Is the bullet you are trying with the same one that was fired from the cases previously? Maybe you've got some .311 - .312 bullets and thought they were .308? Just thinking out loud here...
 
Any ideas? I would expect the neck/mouth to be loose enough as to allow a bullet to be pushed in the the case with no resistence :confused:

Yes, it should be. Better get the caliper out. Measure the bullet diameter, measure the neck diameter. Brass expands tightly in the chamber, and elasticity shrinks it back down a tad after the pressure event, but it shouldn't shrink that much. Perhaps the case mouth hit the bench or something hard on ejection and is slightly oval?

Good luck.
 
What does your brass length measure? Have you trimmed them yet? It's possible that they may have grown in length enough to have formed a kind of a crimp at the mouth from hitting the front of the chamber on that last firing. Also, what about a chamfer on the inside of the mouth? Make sure of these things first before hitting any panic button. Are you trying a flat base bullet or boat tail?

Rooster
 
One other thing to consider.....what load are you shooting in this 30-06?
A very light load will not expand the necks enough to accept a new bullet freely.
Regards, Eagleye.
 
Are you tumbling wet with stainless steel media?

Did you have the same problem with a standard full length resizing die and lubed cases?

What is the diameter of the mandrel?

Do you have longitudinal pucker marks on the case necks?

Did you polish and remove any burs on the collet and collet sleeve?

 
We need to know at what point your necks are getting too small. Lots of things to do.

Caliper your bullets to make sure you have .308s.
Caliper the inside of your tight necks and tell us what you have.
Do so after sizing and tell us what you have.

Try to chamber a freshly fired piece of brass.
Try to chamber one after tumbling.
Try to chamber one after sizing.

Make up some dummy round with your bullet seated but no primer, powder or crimp and put chamber it. Tell us what happens.

Did you have any trouble feeding your bullets into the chamber?

It's a little odd. If you can't find a simple problem shortly, maybe look into casting the chamber.

I want to see how this one works out.
 
Is the bullet you are trying with the same one that was fired from the cases previously? Maybe you've got some .311 - .312 bullets and thought they were .308? Just thinking out loud here...

For sure the same bullet. I only have one box of .308 bullets and I checked them anyway. All .308

Yes, it should be. Better get the caliper out. Measure the bullet diameter, measure the neck diameter. Brass expands tightly in the chamber, and elasticity shrinks it back down a tad after the pressure event, but it shouldn't shrink that much. Perhaps the case mouth hit the bench or something hard on ejection and is slightly oval?

Good luck.

I extracted all the cases gently in to my hand. Bullets are .308

What does your brass length measure? Have you trimmed them yet? It's possible that they may have grown in length enough to have formed a kind of a crimp at the mouth from hitting the front of the chamber on that last firing. Also, what about a chamfer on the inside of the mouth? Make sure of these things first before hitting any panic button. Are you trying a flat base bullet or boat tail?

Rooster

Flat base speer 2053 bullets. Have not chamfered anything yet, and I just trimmed them all to the trim to length before the last firing.

One other thing to consider.....what load are you shooting in this 30-06?
A very light load will not expand the necks enough to accept a new bullet freely.
Regards, Eagleye.

That's good thinking, but I am getting up there - all of them were 2725 - 2850 ish on this last session. Pretty good velocity, good gas seal and clean necks.

Are you tumbling wet with stainless steel media?

Did you have the same problem with a standard full length resizing die and lubed cases?

What is the diameter of the mandrel?

Do you have longitudinal pucker marks on the case necks?

Did you polish and remove any burs on the collet and collet sleeve?


I am using a vibratory tumbler with corn cob media. These cases were sized with a full length die, but I wanted to neck size the next loads. That's how I noticed something weird, I wanted to measure before neck sizing so I could size them .001 smaller than the bullets. Haven't looked at the collet, but I did size a few cases and the look great.

We need to know at what point your necks are getting too small. Lots of things to do.

Caliper your bullets to make sure you have .308s.
Caliper the inside of your tight necks and tell us what you have.
Do so after sizing and tell us what you have.

Try to chamber a freshly fired piece of brass.
Try to chamber one after tumbling.
Try to chamber one after sizing.

Make up some dummy round with your bullet seated but no primer, powder or crimp and put chamber it. Tell us what happens.

Did you have any trouble feeding your bullets into the chamber?

It's a little odd. If you can't find a simple problem shortly, maybe look into casting the chamber.

I want to see how this one works out.

All great suggestions. Bullets are for sure .308.


I think I just figured it out. It is only small where I crimped the cases with the lee factory crimp die! I can measure the inside of the neck behind the crimp - 3.14 and on the area at the end it is about 3.05 ish. The inside diameter where the crimp is is springy so its a little tricky to get a good measurement, but you get the idea.

I suspected that the Lee FCD was causing this, but I put too much faith in the guy I talked to from Lee who told me that this wasn't possible. My collet sized cases are now coming out at .307 the way I have it set now so I am happy with that.

Thanks guys! These little mysteries are where I am really learning about reloading because it really forces me to think things through.
 
One other question, how new is the gun, some chambers are machined tightly, and others are more loose on specs, and a tighter neck is good, usually .001 smaller then the bullets.
 
The gun is from 1980, but it's very gently used. It sat in a safe for a long time. It can't have anything to do with the rifle because everything was normal when I did not use the lee factory crimp die. The ends of the cases had tight necks from the lee FCD. When did not use the lee FCD the ends of the necks were not tight after they were fired.
 
Why would you crimp for a Remington Model 700?
Factory loads are crimped and that after the first firing the case is resized and the mouth of the case chamfered.
There are chamfering tools that are about 45 degrees and the VLD(very low Drag) style that is about 22-25 degrees.
The VLD allows for far easier insertion of the new bullet.
Measure the outside neck diameter of a factory round, and do the same with your resized round, and again with your loaded round.
The neck of the loaded round should be about 0.002" larger than the resized round.
Have your reloading skills progressed to the point where you are doing Outside Neck reaming. This will become necessary if the chamber of your rifle is tight or as the neck thickness increases with time.
 
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