# Sizing the whole neck?

**URL:** https://forum.bulletcentral.com/t/sizing-the-whole-neck/94
**Category:** Micron Precision
**Created:** [January 13, 2026, 6:05am UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94 "2026-01-13T06:05:38Z")
**Posts on this page:** 11
**Page:** 1

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### Author: ![ShaunW](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/shaunw/32/72_2.png) [@ShaunW](https://forum.bulletcentral.com/u/ShaunW)
#### Post date: [January 13, 2026, 6:05am UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/1 "2026-01-13T06:05:39Z")

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I have a 6BR micron bushing die and it only sizes part of the neck. Is there a way to make it size the whole neck?

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### Author: ![rael.harris](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/rael.harris/32/26_2.png) [@rael.harris](https://forum.bulletcentral.com/u/rael.harris)
#### Post date: [January 14, 2026, 12:15pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/2 "2026-01-14T12:15:30Z")

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Hi Shane,

Back when we first released the dies, they shipped with a bushing retainer cap that allowed the bushing to float a little so that necks would size partially (this was a preferred method for bench rest Reloader).

Does the top of your cap say, “Partial Neck Size” on it? If so, we need to set you up with a “Full Neck Size” bushing retainer cap.

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### Author: ![Dakotaman](https://forum.bulletcentral.com/letter_avatar_proxy/v4/letter/d/58f4c7/32.png) [@Dakotaman](https://forum.bulletcentral.com/u/Dakotaman)
#### Post date: [January 28, 2026, 2:52pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/3 "2026-01-28T14:52:20Z")

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Shaun, are you aware that partially sizing the neck is the preferred method of most precision shooters. It helps ensure that a fire-formed cartridge is perfectly centered in the chamber regardless of side-to-side pressure from the ejector or extractor to push it off-center. I’ve never used any other method if I want to shoot in the 0.0’s. You will have to turn the necks for consistent brass thickness before fire-forming to ensure that the bullet is centered when it is in the chamber.

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### Author: ![ShaunW](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/shaunw/32/72_2.png) [@ShaunW](https://forum.bulletcentral.com/u/ShaunW)
#### Post date: [February 15, 2026, 1:40am UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/4 "2026-02-15T01:40:59Z")

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This is a picture of the top of my die I don’t see anything saying partial.

 ![IMG_5930](https://forum.bulletcentral.com/uploads/default/original/1X/fe57e771be5feabe8fc86c955074dcdb77d0e7e9.jpeg)

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### Author: ![ShaunW](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/shaunw/32/72_2.png) [@ShaunW](https://forum.bulletcentral.com/u/ShaunW)
#### Post date: [February 15, 2026, 1:49am UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/5 "2026-02-15T01:49:19Z")

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Thanks for the information. I’ve removed my ejector but I have an extractor. I’ve considered turning my 6BR brass now that I have more practice turning necks. I would like a little more clearance. Oh and I’d like to shoot in the zeros!!

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### Author: ![rael.harris](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/rael.harris/32/26_2.png) [@rael.harris](https://forum.bulletcentral.com/u/rael.harris)
#### Post date: [February 16, 2026, 4:16pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/6 "2026-02-16T16:16:57Z")

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Hi ShaunW,

To get back to you on the image you sent. An FL Cap should be fully sizing the neck. We’d be happy to exchange it for you if that is what you want.

May I see a picture of the neck of a sized piece of brass?

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### Author: ![ShaunW](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/shaunw/32/72_2.png) [@ShaunW](https://forum.bulletcentral.com/u/ShaunW)
#### Post date: [February 21, 2026, 8:03pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/7 "2026-02-21T20:03:27Z")

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![IMG_5946](https://forum.bulletcentral.com/uploads/default/original/1X/e2ba60736aa2abd267c2baae7d8b9f72e829e212.jpeg)

I don’t know if this matters but I’m using a Short action customs neck bushing.

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### Author: ![rael.harris](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/rael.harris/32/26_2.png) [@rael.harris](https://forum.bulletcentral.com/u/rael.harris)
#### Post date: [February 23, 2026, 9:48pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/8 "2026-02-23T21:48:32Z")

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Hi Shaun,

Yes, that could have an impact.

Our dies are designed to allow the bushing to "float” when sizing necks. I’m not sure how to explain this but if the SAC bushing is more ‘squat’ or vertically shorter than our Micron (or Redding) Bushings, then it would float up to the hard stop caused by our bushing retainer cap before any actual sizing on the neck begins.

What is the height of that bushing from top to bottom?

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### Author: ![ShaunW](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/shaunw/32/72_2.png) [@ShaunW](https://forum.bulletcentral.com/u/ShaunW)
#### Post date: [February 25, 2026, 11:01pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/9 "2026-02-25T23:01:31Z")

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It measures 0.3795 according to my calipers.

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### Author: ![rael.harris](https://forum.bulletcentral.com/user_avatar/forum.bulletcentral.com/rael.harris/32/26_2.png) [@rael.harris](https://forum.bulletcentral.com/u/rael.harris)
#### Post date: [February 27, 2026, 5:50pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/10 "2026-02-27T17:50:42Z")

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Our bushings measure in at a height of 0.3750”. That’s odd that you are not getting full neck sizing from the bushing you are using.

If you want you can send the die in with some pieces of brass and we can look at it for you. Please make a ticket at [Help Center](http://bulletcentral.com/help) .

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### Author: ![Dakotaman](https://forum.bulletcentral.com/letter_avatar_proxy/v4/letter/d/58f4c7/32.png) [@Dakotaman](https://forum.bulletcentral.com/u/Dakotaman)
#### Post date: [April 19, 2026, 2:45pm UTC](https://forum.bulletcentral.com/t/sizing-the-whole-neck/94/11 "2026-04-19T14:45:50Z")

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On 6PPC, I turn necks on every reload. On most others I turn them about every 3 reloadings depending on how the necks measure. On my 1,000 yard competition reloads, I either use custom chamber-sized dies or I neck size only. My results have shown that group size diminishes with this approach. To shoot zeros, the priorities are 1. the shooter, 2. the barrel, 3. the bedding, 4. the load (bullet, powder/charge, seating depth and case uniformity), 5. the trigger (crisp & about 1.5 oz) and finally 6. the optic (need one with high magnfication and zero parallax… there are about a dozen that work fine.
