Bushing Dies: Please educate me

Bushing vs non bushing sizing dies



Hornady Match Grade Sizing Die - How to select the bushing your cartridge requires

I am a rifle reloading newbie (.223/5.56, .300 BLK, .308) so I will bow out for other members with more experience in rifle cartridge reloading to answer the why.

Ask me about semi-auto pistol reloading, particularly 9mm and I am all ears.

A fixed-neck die is usually reamed to underside the thinnest neck it will see, so the expander can open it to whatever the manufacturer considers appropriate neck tension. That's a lot of work on most brass, 0.005-0.010 undersizing then expanding.

A bushing die lets you set your neck sizing to match your brass neck: thick, thin, turned, etc. If your brass is concentric and consistent, you can even skip the expander. You can also swap bushing for additional undersizing as the necks harden and exhibit more springback.

Some claim better concentricity, but that's dubious; bushings can float off axial, but a fixed die is concentric (or not) every time.

Besides being able to control how much you squeeze the neck down most can size loaded ammo with the bushing removed, aka Body die (Redding Type S). Unless you having a custom sizing die made to fit your chamber with the spec you use for the brass these are next best thing. The bad thing is that you normally end up with a lot bushings depending on who's brass your using. By changing size and how far you size the necks you can control your neck tension.

For the average shooter there is probably not a lot gain. But if your after the most accuracy you can get, every thing is on the table. The dies is just 1 part of the larger puzzle.

The video and the other guys pretty much covered it. Personally I'm not a fan of bushing dies unless you are turning case necks for a tight chamber.

A regular full length sizing die oversizes the neck and then you drag it over an expander so make the inside diameter uniform. This works well when you have the huge difference in specs in brass.

A bushing die lets you get the size that you want without the excessive working of the brass. But, if the neck walls are not uniform, and none of them are, you're creating as much tolerance as you are trying to reduce. And if you turn case necks for a factory chamber you are creating room for even more expansion, working your brass even more. Thats the reason that I'm not a fan.

I have a few tight neck chambers that I neck turn for and I do size with bushing dies. I often run as little as .0015 neck wall clearance. This puts me working the brass to a very minimum. Even the premium brands of brass have uneven neck wall thickness. Brands like Lapua, Norma and RWS. They are very good, closer than most of the more common and lesser expensive brands, but they vary some.

I also have a dedicated beer fridge and you are welcome to stop by if you are ever around central Arkansas.

OP

"...The more I learn about reloading/handloading, the more I realize I have so much more to learn...."

You have NO idea. it is a never ending learning process and a relatively expensive one. There are at least 20 variables, each one more or less having an impact on results when handloading. Go slow and correct with different equipment, if unsatisfied, at a later date. One more piece of advice. Never change more than one variable at a time. If you do, you will not know which one improved results and which one didn't.