Comments on: Optimize Neck Tension with Bushings, Expanders, and Annealing

By: ewetho

ewetho — Mon, 28 May 2018 14:17:17 +0000

Mark C,
The article before getting to the bushing dies were you can set the diameter neck via interchangeable bushings for where you are correct..
It talks about standard dies which just oversized the neck smaller and then use an expander ball/mandrel to set neck tension. So the last operation to the hardening brass would be expansion so springback would be a contraction. So MH noted what I had.

By: Mark C

Mark C — Wed, 28 Mar 2018 15:03:09 +0000

I don’t think MH read the article correctly. If you squeeze the neck down 0.003″ and then the case springs back out 0.001″ after you stop squeezing it, the net reduction is in fact 0.002″ which gives you “neck tension” of 0.002″.

By: MH

MH — Tue, 27 Mar 2018 14:14:09 +0000

I called Redding once upon a time to ask for expander balls to run in conjunction with sizing bushings to refine neck tension even further… but the guy on the phone didn’t get it… I wish someone would.

I’d like to get expander balls in 0.0002″ increments so the bushing gets you close from the outside of the case and the expander ball tweaks it from the inside where it counts most.

By: MH

MH — Tue, 27 Mar 2018 14:10:07 +0000

There’s a mistake in this article where he recommends using an expander that is 0.003″ smaller than the bullet plus .001 spring back to get 0.002″ neck tension… Uhhh that math works out to 0.004″ of neck tension guys…

We’re talking about expander balls here… not sizing bushing… right?

If there is 0.001 spring back then you need 0.001 smaller than the bullet… not 0.003″

By: Bruce

Bruce — Tue, 27 Mar 2018 01:08:48 +0000

Tungsten Carbide expander balls remove the need for any lube and seem to also ‘iron-out’ any roughness inside the neck. They don’t wear as fast as the steel ones and they don’t “squeak”.

My major accuracy heresy is the use of the Lee ‘factory crimp” dies.

You can effectively applu “neck-tension” to any degree desired with these. they may shorten the life of the case, but, if you are annealing on a regular basis, this is not such a problem.

I’ve been using them since they were first introduced, starting with the .223 Rem. Initially the requirement was for a method of stopping bullets moving in the case every time a magazine rifle was fired. Then, I discovered that not only did the chronographed velocities SD tighten up, so did the groups.

YMMV.

By: John Whidden

John Whidden — Mon, 26 Mar 2018 18:38:33 +0000

Mike, we have both bushings and expanders for our dies that do what you ask.

John Whidden

By: Jim K

Jim K — Tue, 30 May 2017 12:17:29 +0000

John Whidden (a multi national champion) said he found that case lubes that were lanolin based tended to dry and glue the bullet to the case neck over time. He prefers a popular aerosol spray lube that doesn’t tend to glue the bullets.

By: Mike H

Mike H — Thu, 25 May 2017 18:15:14 +0000

Just as neck sizing bushings are available in different sizes, I’ve always wanted to purchase expander balls in specific sizes.

My dream is to combine both.

Imagine having control over both the amount of compression and expansion.

After all, the inside diameter is most important in the end, but without combining both, we live a life of struggle to get neck tension just right.

By: Mike

Mike — Thu, 25 May 2017 05:33:25 +0000

Last year a made a test, I prep 120 of a known good shooting load and I shot one 5 shots groups for accuracy and one 5 shots string for speed. Over a period of ( 1 year, every month ) my speed increased sd/es got lower numbers and the accuracy improved. I tried to keep the shooting condition close to the same all the time. My conclusion is that the only factor that would have change is the neck tension, The bullet would stick to the neck over a period and after 6/7 months no more speed increase was observe. I know this is contrary to most belief especially saying that the accuracy was improved over time, and I would suggest that you try your own test. Neck tension or retention if I could say it like that is not an absolute measure it will change over time,and each load is different depending on the condition they where first loaded at and how much the bullet will stick to the neck.We try to load the same as possible by measuring the size of the neck but in reality we should measure the force needed seat and/or pull the bullet.
Mike