Hello. I’m new to reloading and I’ve been doing 300 blk. My formed empty brass fit the case gauge just fine. It’s when I seat the bullet that I’m having issues.

When I put the bullet in the case gauge, it gets stuck, like so https://i.imgur.com/IMy7e5C.jpg
But if I spin the brass in the case gauge, I can get it to go in flush. This tells me there’s some runoff or some type of bullet misalignment going on.

I really can’t be confident that my dies are set up correctly. The forming die produces brass that fit in the case gauge and the seating die is set up in a way that I’m getting the correct OAL. One person recommend to me to spin the brass halfway when it’s in the press, that didn’t seem to help. Another said to check the neck wall thickness because it can’t exceed .012. The brass appears to be fine. If someone could offer me suggestions, I would be grateful.

How about making some simple measurements..first at the middle of the case mouth, make 2 measurements 90* to each other..then the same 2 measurements on the case shoulder, just below the shoulder, then just above the case head.. Do this on both a sized case and a loaded case..

Empty: Middle Case Mouth: 0.328, 0.327
Case Shoulder: 0.348, 0.348
Below Shoulder: 0.360, 0.360
Above Case Head: 0.373, 0.372.5

Loaded: Middle Case mouth: 0.331.5, 0.330.5
Case Shoulder: 0.347, 0.348
Below Shoulder: 0.359, 0.360
Above Case Head: 0.372, 0.371.5

Here is the saami spec for your cartridge...

Attached File


Attached File


Looking at your measurements, I would try tightening the die down a bit more and size them a bit more..the measurement just below the shoulder seems pretty tight... this also gives you the rest of the measurements that you can compare as well...It well could be excessive bullet runout as well, but you will need a concentricity gauge to check that...

So I should tighten the sizing die, the expander ball or the seating die?

I would try screwing the sizing die in just a bit...think 1/4 turn or so and that should both push the shoulder back a  bit more plus reduce the outside diameter at the shoulder a bit...You should be able to see it in your measurements...doesn't need much, .001-.002" tighter...If that doesn't help then you need to check concentricity of the seated bullets...but I think tightening the sizer will do it..

That fixed it. Thank you for your help.

Awesome..just a lucky guess on my part...