Is there any benefit to bushing neck sizing if I don't turn case necks?

[IMtheNRA]

Considering that even the best brass seems to have some neck thickness variance, is there any benefit at all to bushing neck sizing when making precision target ammo without neck turning the brass?

I suspect it may even be counter-productive, as thickness imperfections will be transferred from the OD to ID of the neck, thereby introducing inconsistencies in neck tension.

What do you think? Bushings (Redding bushing neck sizer) or expander balls for un-turned necks?

 

[Walkalong]

What application?

That said, with bushings, you get rid of the dreaded expander ball. That is never bad.

Without turning necks you will need to match the bushing(s) to the neck thickness of your batch of brass. Change to a thinner necked brass, you have to change your bushing.

So no, you don't have to turn your necks to use them, but to get the most out of them, turning necks, or at least cleaning them up, is going to be more consistent as far as neck tension goes.

To go farther than that would be to use a custom barrel with a tight neck, turn your necks to fit, and adjust the bushing size to get the neck tension and accuracy you are looking for..

Oh yea, seating the bullets moves the imperfections back to the outside. More or less, as it isn't an exact science.

 

[IMtheNRA]

The application would be for precision .223 ammo for a bolt action rifle. Not bench rest, but more casual precision shooting that stops short of turning case necks. I know I shouldn't use the bushing die for my ARs, because they produce occasional dented case mouths and I'm pretty sure the expander ball is the only way to fix those.

The inconsistency that worries me is the wall thickness variance of the case mouths, especially on brass that has been used and resized several times. I've noticed occasional +/- 0.001 from one side of the mouth to the other. Sometimes, 0.002

Wouldn't applying an outside bushing to an imperfect case mouth such as that pretty much guarantee bullet seating runout?

 

[USSR]

Redding bushing dies were pretty much all that was used when I shot 1,000 yard F Class, and nobody bothered to turn necks.

I suspect it may even be counter-productive, as thickness imperfections will be transferred from the OD to ID of the neck, thereby introducing inconsistencies in neck tension.

Seating a bullet acts just like a mandrel - any ID imperfections are immediately transferred back to the OD. The beauty of bushing dies is the ability to get EXACTLY the amount of neck tension you want. Typically we used about .001" neck tension. One thing to remember, if you are sizing your necks down more than .005" from their fired size to their resized size, use an intermediary size bushing before using your final size bushing to prevent excessive runout. For example, if your fired .30 caliber OD necks measure .343" and you want to bring them down to .335", use something like a .338" bushing followed by a .335" bushing. Hope that helps.

Don

 

[IMtheNRA]

Don - when you shot 1,000 yard F Class, did you use a semi-auto? If so, did you have dented case mouths and did you use the bushing dies on them, then relied on the mandrel effect of bullet seating to straighten out the case mouth? I ask this because I'm hoping for an excuse to use the bushing die on my AR-fired brass. After FL body sizing it, of course.

My neck OD is surprisingly consistent. Almost all brass, Lapua and Winchester has OD of 0.2495 loaded and 0.2540 fired.

 

[USSR]

IMtheNRA,

No, if you're serious about 1,000 yard competition, you shoot a boltgun. For dented case mouths, you use a punch or nail seater; something with a tapered shaft to round out the case mouth prior to sizing the neck.

Don

 

[Walkalong]

My hi-tech case mouth dent remover. I don't know what it really is.

 

[USSR]

Looks like the top of a fence.

Don

 

[stubbicatt]

Don - when you shot 1,000 yard F Class, did you use a semi-auto? If so, did you have dented case mouths and did you use the bushing dies on them, then relied on the mandrel effect of bullet seating to straighten out the case mouth? I ask this because I'm hoping for an excuse to use the bushing die on my AR-fired brass. After FL body sizing it, of course.

My neck OD is surprisingly consistent. Almost all brass, Lapua and Winchester has OD of 0.2495 loaded and 0.2540 fired.

IME, one should FL resize for an auto rifle. The bushing FL dies that I use are Whidden, which are used exclusively in bolt actioned rifles. I have found that there is a portion of the neck, and a portion of the shoulder where it meets the neck, that remain untouched by the die. I believe that this unsized portion of the neck and shoulder help to center the cartridges in the chamber. I do not experience any sort of difficulty closing the bolt on a cartridge which has been sized in this manner to set back the shoulder .001 to .002"

My experiences with autoloaders has been only with standard FL dies. I would be reluctant to deviate from that practice, as most autoloaders do not come with a safety sear that will prevent the rifle from discharging should the bolt not go fully into battery. In essence I would be concerned that the unsized portion of a cartridge resized in a FL bushing die might introduce an OBD.

 

[243winxb]

Bushing die AR 223 - Unturned Necks

Is there any benefit to bushing neck sizing if I don't turn case necks?

Yes, the simple fact that many standard dies over work the brass, sizing the neck smaller than needed. Then the expander rips it back open. Buy a Redding Type S FL sizing die and a few bushings. Test with and without the expander. See what your rifle likes. The correct bushing will produce a very light drag on the expander, when used. This does not seem to hurt a thing in my 243win with unturned necks. I lube the inside of the neck, because i am using the standard expander. The carbide button/expander would be a better choice. But for an AR, i would not bother, unless you have a very accurate match grade barrel. The bushing should be 2 or 3 thousands smaller then the loaded rounds smallest neck diameter.

 

[Walkalong]

The correct bushing will produce a very light drag on the expander, when used

That is a good way to set it up IMO.

 

[atblis]

My experiences with autoloaders has been only with standard FL dies. I would be reluctant to deviate from that practice, as most autoloaders do not come with a safety sear that will prevent the rifle from discharging should the bolt not go fully into battery. In essence I would be concerned that the unsized portion of a cartridge resized in a FL bushing die might introduce an OBD.

The Ar15 is designed such that the firing pin does not protrude from the bolt face unless the bolt is rotated and locked into the barrel extension. It's darn near impossible for an AR15 to fire out of battery due to the hammer striking the firing pin and thus the primer with the bolt not locked. I use the Redding Full Length S die for all my AR15 stuff. No issues with any of my guns so far.

For high volume loading for autoloader brass (AR15 and M1), I use a Lee collet neck die as the very first step. It does a very good job of straightening out dinged up necks.
https://www.youtube.com/watch?v=ivk5pfOlrKQ

Also, the Lee collet neck die is (in theory) tolerant of differences in neck thickness. It's a very interesting die really.

 

[flashhole]

You will get some benefit from using the bushing dies but I agree with the premise you stated in your opening post ... the transfer of non uniform neck thickness will always be there when using a bushing die (or any other sizing die for that matter) and it will always account for some degree of runout governed by the degree of thickness variation in the neck.

Bushing dies will provide best results with uniformly neck-turned brass. But I believe you already knew that.

 

[GLOOB]

What do you think? Bushings (Redding bushing neck sizer) or expander balls for un-turned necks?

For accuracy, the first thing I would try is a Lyman M die for unturned necks. Then a mandrel-based neck-sizing die. Expander balls don't necessarily leave a uniform ID, either. They can stretch and deform necks.

For extended brass life, sure, use any neck sizing die.

 

[flashhole]

GLOOB makes a good point about the mandrel based neck sizing dies like the one made by Lee Precision. It works well and you can get a custom mandrel if needed.

Another option is to have a FL sizer honed to the exact dimension you need. I know Forster provides this service and I believe Redding does too.

 

[mugsie]

Walk along,
A plum bob I suspect.

 

[Walkalong]

Kind of small for that. Could be though. The bottom piece (A screw) is screwed into the larger part.

 

[scootter31]

Lamp Finial?

 

[lightman]

This has be argued before, but in my opinion, no! Each side of the argument has their reasons, some of which make sense and some don't.

I use a polished center punch to round out bent case mouths. The pic of that do-dad is interesting, looks a little like a plumbob.

 

[USSR]

Ah, Walkalong's mystery tool. We may never know.

Don