Bushing sizing dies

[M99]

It seems that most precision shooters either use a Bushing sizing die or one custom to their chamber. I prefer using Whidden's custom dies instead of a bushing die. However, I question why a Bushing die would help with precise neck tension since after sizing the neck is always undersize and it is either the sizing ball or a mandrel that sets the final neck diameter and tension. My thought it that I use a custom die to set the shoulder back precisely and I use a Sinclair Expanding mandrel to set the final neck diameter.

I'd be interested in hear other thoughts. What am I missing?

 

[Dusty Stevens]

Why would you use an expander on a bushing die? Whidden makes custom fl sizing dies with bushings and no expanders. Thats my recommendation

 

[snakepit]

Buy a Whidden Expander Ball Kit for your Whidden Non-Bushing Sizer Die which comes with five expander balls to set the neck tension at .001, .002, .003, .004 or 005". No need for bushings or expander mandrels.

www.whiddengunworks.com/product/expander-ball-kits-and-sets/

 

[dsculley]

You don't need an expander when using a bushing. You are sizing the neck down only the amount you want. You are not oversizing then expanding to the desired size.

 

[mikecr]

If the die allows for 5thou interference fit with an expander choice, it's way oversizing necks already..
The problem with not using die expansion is that you are then using your bullets to perform this function.

 

[Dusty Stevens]

And expanders stretch the neck in addition to over working it. Your brass will measure all over the place

 

[chkunz]

Why would you use an expander on a bushing die? Whidden makes custom fl sizing dies with bushings and no expanders. Thats my recommendation

I found that I got more variation in neck internal diameter when I only used the bushings, probably due to the variation in brass spring back. I get more consistent final neck internal diameter if I size down an extra 0.001 with the bushing and then bring the neck internal diameter back to what I am looking for with an expander mandrel. Also, some claim that this procedure tends to push the variation in brass thickness to the outside and they think that is a good thing but I have not tried to measure this.

 

[Falfan2017]

I found that I got more variation in neck internal diameter when I only used the bushings, probably due to the variation in brass spring back. I get more consistent final neck internal diameter if I size down an extra 0.001 with the bushing and then bring the neck internal diameter back to what I am looking for with an expander mandrel. Also, some claim that this procedure tends to push the variation in brass thickness to the outside and they think that is a good thing but I have not tried to measure this.

Could be difficult to meaningfully measure that but I did notice better groups when I took out the expander ball and started using an expander mandrel in my 6 br.

 

[cw308]

The only way to size without the expander is if your neck turning your brass and your outside diameter is true to the inside diameter. Doesn't matter if your using bushing or custom dies . Brass thickness is different from case to case or brand to brand . Wouldn't sending your fired brass to a company for a custom die , what happens when you use up that brass . Unless you neck turn cutting the necks to the same thickness then yes a custom die or bushing dies without the expander using the bullet as the expander when seating when the necks are trued. I use the standard RCBS F/L die with the expander , lube the inside of the necks , Redding Competition shellholder set of 5 to size to .0015 - .002 , I don't neck turn or use heat , runout is on the average .001, may not shoot one hole groups but at 200 yards my 308 shoots consistently .5 that's on me , my rifle for sure shoots better .

 

[Dusty Stevens]

I found that I got more variation in neck internal diameter when I only used the bushings, probably due to the variation in brass spring back. I get more consistent final neck internal diameter if I size down an extra 0.001 with the bushing and then bring the neck internal diameter back to what I am looking for with an expander mandrel. Also, some claim that this procedure tends to push the variation in brass thickness to the outside and they think that is a good thing but I have not tried to measure this.

Any shooting that needs good enough accuracy to get a die made needs to have the necks turned anyway

 

[M99]

Thanks for those reply's and explanations. I do neck turn my brass, and I also anneal every loading, so my brass seems to last pretty well. I did not previously understand that when using a bushing die, you typically did not need to expand afterwards. I have measured several times and found that my Custom Whidden dies without any expander ball, sizes the necks down about .003 less than what my Sinclair expander mandrel sizes them up to, and that gives me about the .002 per side neck tension I am looking for. So it seems that what I am doing is about right.

 

[cw308]

M99
Being that you neck turn and anneal your necks your brass is just about perfect and needs very little to do in sizing your neck tension and dimensions , the expander could add more of a problem . Not much more you can do in case prep , does take time .

 

[LVLAaron]

* I anneal every firing.
* I full length size w/ the use of the appropriate redding competition shell holder. (Allows consistent shoulder bump, they're cool, and makes it super easy to always have the same shoulder bump)
* I use a bushing that gets me as close as possible with the next step in mind
* I use an expander mandrel that's .002 under the bullet diameter.

It works for me, my seating pressures are very consistent, and you can lay a straight edge across my water line.

 

[cw308]

LVLAaron
Never got into annealing my brass , many of my shooting friends do. Last season I was getting 25 reloads out of my 308 cases , when one showed a loose pocket or a crack at the neck , I dumped them all ( 30 ). This season I'm testing 3 lots of 30 and rotating each week. Groups are consistent and seating is smooth . I wet tumble with pins and lube the inside of the necks when seating . I wouldn't know if the cases are getting hard , can you see a difference in your groups by adding heat?

 

[LVLAaron]

LVLAaron
Never got into annealing my brass , many of my shooting friends do. Last season I was getting 25 reloads out of my 308 cases , when one showed a loose pocket or a crack at the neck , I dumped them all ( 30 ). This season I'm testing 3 lots of 30 and rotating each week. Groups are consistent and seating is smooth . I wet tumble with pins and lube the inside of the necks when seating . I wouldn't know if the cases are getting hard , can you see a difference in your groups by adding heat?

For long range / competition stuff, yes. I can. It's really just about having an absolutely consistent experience. And expensive brass lasts longer.

 

[cw308]

LVLAaron
I'm not shooting hot loads , my maximum range is 200 yards do to the ranges in my neck of the woods is 200 yards . I found a good accurate mild load the consistently shoots well .. My brass may not be totally fire formed and lasts many reloads without a hint of a problem , the three different brands are FC , HSM and ADI not at the top of the list for sure , my groups are average .5 at 200 , my not win contests but love bench shooting with my friends . And kicking things around with my forum friends , Thanks for answering. Be Well.

Chris

 

[LVLAaron]

Same. I didn't anneal for a very long time, and it was fine. It's just one of those little things you can do. i'm sure some guys take it was far as always wearing the same pair of pants for their ammo loading sessions. I think I know a few of them