What am I doing wrong with sizing brass?

[JAYgs8163]

Hi guys,

I need some help. I've been reloading for about 8 years now. I've run into something that's got me totally frustrated. It's happened a couple of times and I'll be damned if I can figure out what it is.So I just prepped some once fired Norma 7 mag brass. Resized. Trimmed to length and chamfered with VLD trimming bit. Checked length and everything is perfect. Put in my 7 mag Hornady case gauge and fits perfect. I then charged the case and seated a 180 Berger VLD. The problem I have is after seating the bullet the round is not fitting into the case gauge. See pics below. The first 2 pics show the brass only in the case gauge and the last 2 are the completed round. I've had a similar situation recently with a 6.5 Creedmoor. It makes me think I'm not resizing the brass properly. I only full length resize all of my brass. I'm using Redding Master Hunter series dies. I also have a set of Lee and I got the same results. Any suggestions would be greatly appreciated.

 

[JAYgs8163]

Here's a picture of the brass.

 

[JAYgs8163]

Picture of the round.

 

[Bob Wright]

Will it chamber?
I use a headspace comparator to measure spent brass vs sized brass, mic necks before and after loading during initial set up.
The problem with this case guage is you're not getting individual measurements of the critical dimensions as it is either "go or no go.
Not much to go on unless you start measuring fired, to resized brass. Some dimension is being altered after bullet installation.

 

[jimbires]

I've never used a case gauge , but I have a thought . could a bullet be bottoming out in the gage ? will a bullet go through the gauge ?

 

[JAYgs8163]

I've never used a case gauge , but I have a thought . could a bullet be bottoming out in the gage ? will a bullet go through the gauge ?

Bullet passes through the gauge with no interference. Checked that long ago but thanks.

 

[LVJ76]

I've never used a case gauge , but I have a thought . could a bullet be bottoming out in the gage ? will a bullet go through the gauge ?

Me neither, rifle's chambers are my gauges.

Like @Bob_Wright asked, will it chamber?

 

[JAYgs8163]

Will it chamber?
I use a headspace comparator to measure spent brass vs sized brass, mic necks before and after loading during initial set up.
The problem with this case guage is you're not getting individual measurements of the critical dimensions as it is either "go or no go.
Not much to go on unless you start measuring fired, to resized brass. Some dimension is being altered after bullet installation.

It does chamber. I don't have that tool you mention but I imagine I will soon. Any good reads or a link you can share are appreciated.

 

[ShtrRdy]

It sounds like the neck diameter gets to big for the case gauge after seating the bullet.

What is the neck diameter on a loaded cartridge?

 

[Rick Richard]

Belted cases are known not to completely resize all the way down to the belt. Do a search on resizing belted magnum cases and read what Larry Willis has to say. What you are experiencing is not uncommon.

 

[JAYgs8163]

It sounds like the neck diameter gets to big for the case gauge after seating the bullet.

What is the neck diameter on a loaded cartridge?

Standby, I'll get it in a little bit.

 

[Bob Wright]

It does chamber. I don't have that tool you mention but I imagine I will soon. Any good reads or a link you can share are appreciated.

Start here:

Lock-N-Load® Headspace Comparator & Anvil Base Kit - Hornady Manufacturing, Inc

Lock-N-Load® Headspace Comparator & Anvil Base Kit Lock-N-Load® Headspace Comparator The Lock-N-Load® Headspace Comparator extends brass life, improves accuracy, and enhances safety. The gauge measures...

www.hornady.com

There may be some Hornady videos on this official site.
Maintaining brass to chamber fits is really important. This measures your brass shoulder datum to the head and allows you to set your shoulder bump at FL sizing to fit properly (headspace) and prevent excess headspace.
You'll need dial or digital calipers to measure with this guage.
This guage is just one of those needed when setting up brass to fit each chamber one may have.

 

[Stammster]

Belted cases are known not to completely resize all the way down to the belt. Do a search on resizing belted magnum cases and read what Larry Willis has to say. What you are experiencing is not uncommon.

So why did it fit fine in the case gauge after he resized, but not after he seated the bullet? I don't think this is a resizing issue.

BTW, I use a Hornady case gauge on every round I load. Once it is resized, and once I seat the bullet.

OP...Are you running a compressed load? When the loaded round is inserted, does it look like the head is offset in the gauge slightly?

 

[jdyoung]

Standby, I'll get it in a little bit.

Neck diameter, especially at neck/shoulder junction, on both empty and bullet seated cases !!!