What did I do? Case body bulge

[ko1featherweigh]

Reloaded some 3006 and when shooting a handful wouldn’t feed. Upon inspection those that failed to feed all had some degree of bulge in the side of the case. Reloaded some different headstamps during this session but only the barns brass had the issue. All brass was once fired through the same rifle.

 

[A382DWDZQ]

Were the Barnes stiffer to seat or longer cases?

 

[ko1featherweigh]

Were the Barnes stiffer to seat or longer cases?

All brass was trimmed to the same length. I don’t recall bullet seating being any stiffer than others.

I haven’t pulled the bullets yet but I’ll measure case length just incase

 

[pbroski]

Are your loads compressed? Too much powder compression will cause bulges like that.

 

[ItsPaste]

Are you running a full length resizing die, or are these fire formed?

 

[A382DWDZQ]

Check the thickness of the neck wall also. Could be that it’s thicker than the others and so neck tension is a bit stiffer. Seating might be putting too much pressure.t

 

[ItsPaste]

Check the thickness of the neck wall also. Could be that it’s thicker than the others and so neck tension is a bit stiffer. Seating might be putting too much pressure.t

I definitely second this. I've added an extra step to my reloading process for normalizing neck tension of my cases and it's done wonders for standard deviation. You may have come across some super tight cases.

 

[SloppyJ]

I definitely second this. I've added an extra step to my reloading process for normalizing neck tension of my cases and it's done wonders for standard deviation. You may have come across some super tight cases.

What's your process that you implemented?

 

[ItsPaste]

What's your process that you implemented?

I now use an expander mandrel. An extra step in the process, but has produced measurable results.

 

[RockAndSage]

I now use an expander mandrel. An extra step in the process, but has produced measurable results.

I'm only minimally experienced in handloading rifle ammo, but I want to make sure I understand this - using an expander mandrel makes neck inner-diameter uniform, and thereby makes neck tension uniform once you seat the bullet?

How does that work if you're dealing with differences in neck-wall thicknesses? Even if the neck's inner-diameter were uniformed with the expander, wouldn't a thicker neck wall still end up being compressed back into a narrower neck ID when seating the bullet?

 

[Taudisio]

I'm only minimally experienced in handloading rifle ammo, but I want to make sure I understand this - using an expander mandrel makes neck inner-diameter uniform, and thereby makes neck tension uniform once you seat the bullet?

How does that work if you're dealing with differences in neck-wall thicknesses? Even if the neck's inner-diameter were uniformed with the expander, wouldn't a thicker neck wall still end up being compressed back into a narrower neck ID when seating the bullet?

Potentially. In my experience, neck sizing with a die makes it smaller than necessary, and you have spring back after you pull your the expander ball through it. You still have spring back when using an expander mandrel, but that can vary with the length of time you keep the mandrel inside (dwell time). I too have found the expander mandrels to be much more consistent when I am seating bullets.

OP, if you answer the questions asked above, it can help narrow down what the issue might be.