[RYT 2BER]

It seems that no matter what I do I end up with a slight ripple,or fold or line (whatever the term is) in my .40 reloads. The ripple on the brass is exactly where the bottom of the bullet is.

I used to think my dies were set too far low and I was getting too much crimp or something,

But I notice it seems to occur when my bullet is being seated... I have backed out my dies tremendously and it doesn't seem to make a noticeable difference....

Any thoughts on this?

[Zombie Steve]

Your sizer die is bringing the dimensions of the brass down to where it can have a good grip on the bullet again. When you seat a bullet, it's stretching it open slightly.


Start worrying when you don't see it.

[RYT 2BER]

Originally Posted by Zombie Steve

Your sizer die is bringing the dimensions of the brass down to where it can have a good grip on the bullet again. When you seat a bullet, it's stretching it open slightly.


Start worrying when you don't see it.

Understood. And I have been shooting them this way for a while. But I notice factory ammo doesn't seem to exhibit this quality.... Why would mine and not factory?

[shotgunred]

run a piece of brass through your sizer and then measure the inside diameter. Your bullet is probably .400 or .401. measure it?
My guess is your sizer it taking your brass down a little more than that.
Which sizer are you using?

[RYT 2BER]

Originally Posted by shotgunred

run a piece of brass through your sizer and then measure the inside diameter. Your bullet is probably .400 or .401. measure it?
My guess is your sizer it taking your brass down a little more than that.
Which sizer are you using?

I'm using a lee .40 caliber 4 die kit.. But I'll check. More to follow

[Zombie Steve]

Brass has a tendency to spring back a little. Sizing dies tend to go a little small... smaller than factory for sure. Undersized is just fine. Not enough is a problem.

[RYT 2BER]

Originally Posted by Zombie Steve

Brass has a tendency to spring back a little. Sizing dies tend to go a little small... smaller than factory for sure. Undersized is just fine. Not enough is a problem.

Many thanks for the info... Comforting news..

[Zombie Steve]

Sometimes it's referred to as the hourglass look, or a Marilyn Monroe cartridge. Looks goofy, runs like it should. Just a normal part of reloads. Some dies do it more than others. I basically equate it with good neck tension.

[Colorado4Wheel]

Factory ammo does not have nearly as many variables as we do as reloaded. So our sizing brings the brass smaller (this is good for us). What your seeing is the Coke Bottle Shape. Many would love to have sizer like you have that does such a good job.