Type S bushing choice.

[L.Sherm]

Redding tech line tips are exactly what I'm talking about on unturned necks. Bras s necks are far from perfect so if you pull the expander and just use the bushing to resize your necks you will have very inconsistent neck tension your at the mercy of whatever the brass is. By using the expander you have the inside of the neck the same as long as your brass is springing back nearly the same and aren't work hardened differently. By using just the bushing the outside is the same but inside can vary greatly depending on the brass. Outside doesn't matter in your case as long as you have enough neck clearence.

 

[L.Sherm]

Try removing the expander on some unturned brass and just use the bushing and either feel the difference in the seating pressure from your press or try to pull the bullets. People say pulling the expander reduces runout which will if your decapping rod is bent, I use a floating one seems to help.

 

[bigedp51]

Forster full length benchrest dies have a high mounted floating expander. And the expander enters the case neck while the neck of the case is held and centered in the die. Meaning the Forster expander can not pull the case neck off center and induce runout.

Below I have added Forster expanders to all my RCBS dies and Redding dies.

Too many reloaders think that using a expander is the end of the world. And yet Whidden custom dies sells expander kits with five expanders from bullet diameter to .004 under bullet diameter.

 

[Varmint Hunter]

This is much simpler than all the posts make it sound. First - forget about the math calculations because they don't always pan out. Next - dump the expander button because it does nothing good at all when using bushings.

Simply take a loaded round, carefully measure the neck diameter. Subtract .003" and there you have it for determining an appropriate bushing size. This will give you .002" neck tension after an aprox .001" of spring back after the case is drawn out of the sizing die.

 

[L.Sherm]

Everything else be equal execpt neck dia. what controls neck tension inside dia. Or outside?

 

[dok7mm]

By now, I'm sure the OP is totally confused. I suggest that he tries to locate a very experienced reloader, near him, that will set him down and show him how to best get a good consistent neck tension. Hopefully, it will be someone with good measuring tools to find his neck's true thickness variations, check his expander ball diameter, get him set up with right bushing and show him how to solve his problems.

He sounds like he is just getting started and is having some trouble figuring out all the advice and nomenclature used. No criticism intended to anyone, we were all once beginners. A solid mentor will get him lined out.

 

[L.Sherm]

Dok you hit the nail on the head!

 

[eklarsen]

This is much simpler than all that posts make it sound. First - forget about the math calculations because they don't always pan out. Next - dump the expander button because it does nothing good at all when using bushings.

Simply take a loaded round, carefully measure the neck diameter. Subtract .003" and there you have it for determining an appropriate bushing size. This will give you .002" neck tension after an aprox .001" of spring back after the case is drawn out of the sizing die.

The OP has another thread going where his neck is getting pinched in the chamber due to a tight chamber. I dont think it is a simple "select the correct bushing" as it is a combined, brass neck sizing/bushing issue. I am assuming so we all know what that gets me.

 

[bigedp51]

I have Remington .223 cases with .009 neck thickness variations, "WHY" would you want to push neck thickness variations and irregularities to the inside the case neck and not use the expander.

Redding put expanders in their bushing dies for people who do not neck turn.

And a runout gauge and neck thickness gauge will tell you a great deal about your cases and die setup.

 

[Mikecr]

Everything else be equal execpt neck dia. what controls neck tension inside dia. Or outside?

Neither controls neck tension.
Neck tension is bullet grip provided by spring back against an area of seated bearing. Max spring back of expanded necks(which you do with bullet seating) is ~1thou. That spring back force, by area sized/springing back, against bullet bearing, is tension.
Any more interference fit is just excess, and undone by expansion during seating of bullets(which are terrible expanders).
Die makers recommend -2thou of loaded OD for a bushing, based on big neck clearances, leading to higher angle sizing, causing greater than stamped on the bushing, and always expecting followup expansion(pre-seating). It may take trial & error with your chamber & brass & bushings to nail it(until experienced).
This should leave ~1thou spring back against bullet bearing (normal tension).

Pre-seating neck expansion is always the right path, whether necks are turned or not.

 

[Rhovee]

I am new to using a bushing die but not reloading. All the cases have been annealed. I do notice that once fired brass is a lot easier on the way down over the expander ball. Once fired brass also has a lot more consistency to pressure for seating the bullets. At this point I am checking spring back and neck tension with the expander ball which is 1 thou less than bullet diameter. I did this when necking up 26 nosler to 28 nosler and it was very consistent. Probably just over thinking it like usual.

 

[Mikecr]

The only brass that matters is fire-formed. That's what you'll use over & over & over.