Bushing die questions

[jhe888]

I am not sure I understand bushing-type neck sizing dies. They tell you to measure a loaded case and order a bushing .001 or .002 smaller,depending on the maker). No problem, I can do that. What I don't understand is how this varies from a standard die. Say I measure a loaded, factory cartridge. It should be within SAAMI specs for diameter at the neck, and if I measured a sample of the cartridges, I imagine I would come up with something right around the middle of the range. Then I order a bushing that is .001 larger. Why isn't a non-bushing die already that size? Is it that I am going to measure a bunch of loaded Winchester cases, which may differ from a bunch of Norma cases or Remington cases? If that is the case, I guess I need bushings for different brass?

If it matters, I will be buying dies for a Tikka T3 Varminter in .223.

I think I understand why bushing dies are an advantage, but what more can you tell me about that?

Thanks.

 

[Cheechako]

jhe

A "standard" die sizes down the neck a lot more than is necessary and then the expander ball brings the INSIDE of the neck back to the proper diameter to hold a bullet. Because different brands of brass vary in neck wall thickness that is the only way to accomodate the differences. A bushing die sizes the neck to whatever diameter the bushing is from the OUTSIDE only. To do this you have to make measurements of the particular brass you are using. In other words, the bushing can be looked at as a "custom" neck sizing die. The standard die works the brass more than is necessary but for a factory rifle that is not going to be fired too much it is perfectly OK. The brass won't wear out THAT fast and when it does you simply buy new stuff. If you are shooting a lot, where the brass may be re-loaded many, many times,such as a BR or varmint rifle) and you want the brass to last a long time, a bushing die is best. Also, a bushing die MAY result in better accuracy but not always and a lot depends on the accuracy of the cartridge/bullet/barrel combination to begin with. In other words, a bushing die for your 30-30 is a waste of time and money.

ray

 

[Mark Walker in TX]

I'll add just a bit to the excellent response above. IMO, the major benefit to using bushing dies is that you can experiment with what neck tension will provide the best accuracy.

With a regualar die, you have a set amount of tension. With the bushing die, you can try .001 greater, .001 less etc, neck tension, and find the sweet spot for your load and barrel.

The next .223 rifle or barrel that you have, it might like a different amount. Further, different loads like differing tension.

A bushing die just gives you MUCH more control...

Mark

 

[jhe888]

Thanks for the help.

Sounds like you need a regular, full length sizing die to start with anyway, if you are starting with new brass from a new lot.

Or, is brass consistent enough by brand to just take a stab at using a bushing size you have successfully used in the past? Or would you buy two or three bushings and experiment?

What bushings for .223, if the latter approach would work?

 

[Cheechako]

jhe

It's always a good idea to have a FL die on hand. Even benchrest shooters will usually have a 6PPC FL die for those times when you have to resize the whole case. They're cheap and when you need one you REALLY need one.

As far as different bushings, you will need to make some measurements with the brass and bullets you intend to use. For starters I would get a bushing that will size the neck anywhere from .002 to .004 thousandths under the loaded diameter. Load and shoot some. If they work, you're home free. If you think you could possibly improve the load with more or less neck tension then you can get bushings that will bracket the one you start with. Before doing that you might experiment with seating depth first. Usually that has a greater effect on accuracy than neck tension, in my experience anyway. Good Luck.

ray