Setting neck tension - bushing dies or mandrel?

[CamTheBam]

Hi Guys,

How are you preferring to set your neck tension these days? Bushing dies or expander mandrels?

 

[Rick300]

I use a bushing die first and then a mandrel for final tension

 

[JFrank]

Bushing Dies, but...sometimes things aren't what they appear to be for example this is a .262 bushing yet sizes to .261. Im not sure what's up with that so I trust but varify on paper.

 

[BlueWater]

I use a bushing die first and then a mandrel for final tension

@Rick300 , I'm assuming because the brass relaxes a bit after movement ... and that die then mandrel results in a bit more-certain tension, as opposed to mandrel then die. Yes?

 

[AckleymanII]

Bushing Dies, but...sometimes things aren't what they appear to be for example this is a .262 bushing yet sizes to .261. Im not sure what's up with that so I trust but varify on paper.

Micrometer is the proper tool

 

[INTJ]

I go both ways. Mandrel on most, bushing only on some

 

[Nick Caprinolo]

In order for the bushing die to get it right, the necks must all be turned to the same thickness. If there is a variance in neck thickness then there will be a variance in neck tension.

 

[Rick300]

@Rick300 , I'm assuming because the brass relaxes a bit after movement ... and that die then mandrel results in a bit more-certain tension, as opposed to mandrel then die. Yes?

Yes. I tend to prep my brass in advance - except for the final neck tension which I do with a mandrel. So you use a .001 - .002" smaller bushing than you normally would and then expand it back out with a mandrel. I'm not sure if there is as great a benefit with turned necks, but the theory goes that the imperfections are pushed to the outside by using a mandrel. In my very limited experience I have found this produces consistent neck tension as long as it done just prior to bullet seating. I found that if I used the mandrel long before I needed the brass, then the neck tension was all over the place.

 

[Ned Ludd]

I use a bushing first, usually about .001" smaller than I would otherwise use if the bushing were to be the only sizing step, followed by the appropriate diameter mandrel. Using a slightly smaller bushing ensures all the necks will be below a minimum diameter that allows the mandrel to do its job effectively and consistently. Because the mandrel is opening up the neck from the inside in the second step of the process, the case neck will close slightly when the mandrel is withdrawn (i.e. spring-back). For that reason, a mandrel that is approximately .0015" below bullet diameter will yield very close to .002" neck tension.

 

[SeabeeKen]

No matter how their sized, a mandrel sets my final neck tension

 

[gunsandgunsmithing]

Whichever way shoots best is what I do. I try hard not to let what I read on the internet to affect my group measuring abilities.

 

[NZ_Fclass]

We are only trying to set "proper" neck tension - that is the tension that I have found to be the optimum, giving the best group on paper - ie most consistency.
I use some bushing dies - most are not and a mixture of Whidden (6 SLR) Forster (308) and Redding. I have only changed to bushings when the "standard" die did not give the size that I want, For the 308, I use a Forster Benchrest sizing die, with the expander ball removed, giving an easier, smoother size, then follow with a 308 expander. Brass is annealed every time. This gives me 2 thou of tension. Happy days.

 

[D-4297]

Type "S" Bushing Die down to .3065 , and then a .3075 carbide expander . Try to "work" the brass as little as possible . I run the expander the night before loading and have been getting consistent results . I do anneal after every firing .

 

[Coyotefurharvester]

No custom chamber necks, sometimes a mix of brass brands, mostly hunting rifles. Decapping die,fl size, mandrel. Easy accurate shooting ammo.

 

[fatelvis]

Type "S" Bushing Die down to .3065 , and then a .3075 carbide expander . Try to "work" the brass as little as possible . I run the expander the night before loading and have been getting consistent results . I do anneal after every firing .

I see it is popular to use the expander right before loading, as it helps with consistent tension. But is that loaded ammo made with intentions of firing right away, or is it acceptable to be stored for a length of time?

 

[243winxb]

Neck turned/bushing only.
Unturned/bushing & expand.

Sizing down more then .008" in 1 step, may result in a diameter smaller then whats marked on the bushing.

Short range to 300 yards.

 

[JFrank]

Micrometer is the proper tool

Yes but do I really need to use a micrometer to make the point ? We just want consistent bullet hold and consistent group samples and we cant do that without ensuring our tools are consistent as well as practices.

 

[Bc'z]

Yes but do I really need to use a micrometer to make the point ? We just want consistent bullet hold and consistent group samples and we cant do that without ensuring our tools are consistent as well as practices.

No, and you dont need a mandrel to set neck tension either.
Select proper bushing and seat a bullet.

 

[Beiruty]

FS plus mandrel for me.

 

[D-4297]

I see it is popular to use the expander right before loading, as it helps with consistent tension. But is that loaded ammo made with intentions of firing right away, or is it acceptable to be stored for a length of time?

That is something that I've had go both ways . I loaded a Match box of seventy-five rounds that ended up not being used for six months , and it shot mid-to-high 190's , but a low X count . And I've had some that shot low 190's , so I'm not really sure about cause and affect . Shooting steel , it may not matter . Shooting a F class Match , it could . I try to shoot Match loaded ammo within five days at the longest for most consistent results .