Problem with insufficient neck tension?

[Dave R]

I haven't reloaded .308acp for a while. Used up my stash of Laser-Cast bullets. Bought some new Berry's bullets. When I loaded 'em up, I had a big problem with insufficient neck tension. Over half of them wouldn't hold a bullet properly.

I checked as many variables as I could. I checked the settings on my sizer die, expander die, and seating/crimper die. I even tried a Lee Factory Crimp die. Kept getting the same results. Some had fine neck tension, but more did not. After all the adjustments I tried, I got to the point where I could pretty well tell when I was seating a bullet whether there was enough neck tension. The press handle would have less resistance on the rejects than the keepers.

Here are some other variables. Brass is IMI brass, which seems thinner than other brass I have tried. ALL of the rejects were IMI brass. But how come some IMI's held, and others didn't? Could the Berry's bullets be undersized? Could my resizing die be worn out? Its pretty old...

Any other thoughts or diagnostics I could run? Should I just toss the IMI brass? Or could it be something else?

 

[singleshot]

chances are you need to adjust the crimp die. It is surely possible that there is a difference in diameter of the bullets. Typically lead bullets a thousandth or two larger.

It is also possible that the differences in case thickness you mention are part of it but, again, adjusting the crimp die should take care of it.

 

[WSM MAGNUM]

Measure the diameter of the bullets you have from Barry`s? See if they are consistent. If you find no differences in bullet diameter, then I think you still do not have your sizing die adjusted properly.Also check the inside diameters of the cases before sizing them too.

 

[cheygriz]

I would just go back to the Laser-Cast bullets. I'll betcha that if you mike a bunch of the bullets you're having trouble with, you'll find then smaller, and/or inconsistent.

Of course, you could outside turn the case necks on your brass to get them all consistent, and then get a sizing die with a tighter neck, but that would be a "Royal P.I.T.A."

As cheap as cast bullets are, why put up with the hassle?????

 

[HSMITH]

Only having problems with IMI brass? Throw it out and use good brass.

 

[Dave R]

Thanks for the suggestions and diagnostics. At this point, I'm pretty sure its the IMI brass. Or it "might" be my resizer die. Here's the data.

-The Berry's bullets measure consistent at .356.
-I bought some IMI brass sized, primed and ready to load. That brass has worked well. Inside mike on that is .353
-Brass from my resizer die is .354. Two thou of neck tension should still be enough, right?
-After I seat my used brass, about half of them still won't hold the bullet firm enough. After I pull those, they measure .356 inside. No surprise, eh?

To me, that says the brass is just too weak. It measures OK, but after seating, its not holding. Or, possibly, my sizer die may be worn a thou too much, and I need that extra thou to get decent neck tension.

 

[amamnn]

have you tried backing the expander die off a touch?

 

[Dave R]

Yup. I tried backing off the expander die, and making sure I was expanding just the minimum necessary.

 

[Dave R]

Just by way of update--turns out the problem was the crappy IMI brass. I broke down and bought (shudder) some used .380acp brass at a gun show today. Reloaded 100 of 'em tonight. No problems with neck tension. Same dies, same bullets, same settings as before.

Now I just need to find a way to scrounge more .380acp brass.

 

[James A. Mullins]

Hi. Just another thought. Did you buy .355 bullets? IMI has had some problems with inconsist brass. Check the Dia. of your former load. If you have calippers or mikes check your expander. If too large for bullet dia. take the expander and polish with crocus cloth till its .0005 smaller then retry. Before doing anything try your as is die on some other american brass.
James
P.S. You can use an electric drill to tu7rn the expander.