Neck Mandrel, Bushing dies, what works for you the best?

[BowWow]

I have normally used FL sizing dies with a neck bushing and that was it for sizing. Now I'm curious about the neck mandrels.... what works for you guys? I'm going for more consistency from by brass preparation.

Regular FL sizing die?
FL sizing die with a neck bushing?
Regular FL sizing die and then the neck mandrel?
FL sizing die with a neck bushing and the neck mandrel?

 

[Bronsin]

FL Bushing Die w/Mandrel

 

[Bill Norris]

FL sizing die with a neck bushing and the neck mandrel.

 

[PopCharlie]

Full length bushing die, then neck mandrels.

PopCharlie

 

[Monday shooter40]

Bushing S die + carbide mandrel for me. light corn cobb cleaning post process. Be careful of the slippery slope of neck lube effects and cleaning process. Its real and it produces real differences. I can't say I've mastered it by any means. Without lube, a steel mandrel can gaull the inside of necks. Carbide seems to work well for me and seems to hang onto graphite well.

I've tried to run just a bushing die, some of my best loads developed came from not cleaning brass and not touching the inside of the neck with anything but the next bullet, but in a PRS environment, necks get dinged and the bushing doesn't always correct them enough. My OCD won't let seat a bullet in a non perfect neck.

 

[Ray123]

For me, ...a Wilson FL bushing die, a neck mandrel die, and seating with something like Forester Ultra seater, or Wilson micrometer top inline seater...with arbor press..and check TIR....to make sure it's all working.

 

[6BRA]

I used to do that...FL bushing and mandrel....then you gotta step back and say wth is the purpose of the bushing? Annealed every firing...and then there was neck bulge almost .100 thousandths above neck shoulder junction. And then you have to step back and say why? Yes runout was .001, not bad. Good results...but..but........I discovered some things

 

[JMayo]

Bushing die only. No mandrel.

 

[Bottom Fodder]

I full length size/ deprime then with different die I bushing size neck and bump Shoulder then use a mandrel right before I load, Mainly just to be Different more ways than one to skin a cat

 

[Straightshooter1]

I have normally used FL sizing dies with a neck bushing and that was it for sizing. Now I'm curious about the neck mandrels.... what works for you guys? I'm going for more consistency from by brass preparation.

Regular FL sizing die?
FL sizing die with a neck bushing?
Regular FL sizing die and then the neck mandrel?
FL sizing die with a neck bushing and the neck mandrel?

I've tried all of those and the best that works for me is a FL sizing die without an expander ball and the die has been honed so that the neck is only sized .002" less than where I want the OD to be. Then an expander mandrel to bring the neck to where I want it to be. Neck runout is really small, like a TIR that's always less than .001".

 

[Ned Ludd]

I moved to using a bushing die followed by a mandrel several years ago. Before that, I only used a bushing die and would notice occasional variance in neck tension/interference fit when I seated bullets. So I added in the mandrel step and it has largely solved that issue.

As the first sizing step I use a bushing die with a bushing about .001" under the size I would use if the bushing die was to be the only sizing step. For example, I would normally use a .336" bushing with Lapua .308 Win brass if the bushing die step was the only sizing step. After adding in the mandrel step, I typically use a 0.335" bushing, which sizes down the brass sufficiently that the mandrel will actually do some work on all the necks when opening them up. If the selected bushing doesn't size the neck down sufficiently for the mandrel to open the neck back up (i.e. the bushing is too close in terms of sizing the neck to the selected mandrel), the results are less satisfactory.

As the final sizing step, I use a mandrel that is .0015" under bullet diameter (21st Century). This yields a neck tension/interference fit of very close to .002" as the necks will close up about .0005" or so when the mandrel is withdrawn due to spring-back, because the bushing used in the first sizing step yielded a neck diameter slightly smaller than the mandrel. If one desires more or less neck tension/interference fit than ~.002", a slightly smaller or larger mandrel can be selected. The mandrels available from 21st Century come in .0005" increments. Just be aware that a slightly smaller or larger bushing might be necessary in this scenario, as the bushing needs to size the neck slightly smaller than the subsequent mandrel step so that the mandrel actually does some work and opens the necks back up a little bit.

 

[BowWow]

So...... lets say I used a dry lube such as Redding Imperial neck lube (looks similar to graphite), do you guys clean dry lube off or leave it on and seat the bullet?

 

[Bronsin]

I clean it off the outside. I set my bushings and mandrels up exactly the way as Mr Ludd does in the post above you.

 

[Ned Ludd]

If the lube is only on the outside of the neck, meaning you're only sizing necks from the outside with a bushing die, simply wipe it off after sizing. I use Hornady One Shot spray lube to hit both the outside of the case, as well as the inside of the neck if using a mandrel. I spray it liberally enough that wiping it off the outside isn't sufficient, IMO. So I run all the cases through several 5-10 min washes/soaks with Dawn/Lemishine, followed by several rinses with hot water. I typically process 100-200 cases at a time when using this method, so it's really not a huge effort. Cases are then dried as normal before further processing. I wouldn't leave any lube inside the neck unless you purposely mean to do so, as with graphite or other similar lubricants. In other words, using a mandrel step necessitates lubing the inside of the neck, and you probably want to remove that before any further steps.

 

[mikecr]

I don't FL size.
I use a bump die (custom body die), Wilson neck die (bushing), then mandrel expansion.
With this, I set 1thou bump and 1thou interference for ~half-neck sizing length.
My necks are normally turned for 1thou clearance, but of course not for a factory chamber.

 

[BowWow]

Thanks fellas, I'm going to try mandrel and see how it goes!

 

[avidflyer]

I've tried all of those and the best that works for me is a FL sizing die without an expander ball and the die has been honed so that the neck is only sized .002" less than where I want the OD to be. Then an expander mandrel to bring the neck to where I want it to me. Neck runout is really small, like a TIR that's always less than .001".

absolutely spot on....never cared for a bushing that leaves a little of the neck unsized. Honed dies seem to work great...then mandrel up to what
you want.

 

[Papamike]

If the lube is only on the outside of the neck, meaning you're only sizing necks from the outside with a bushing die, simply wipe it off after sizing. I use Hornady One Shot spray lube to hit both the outside of the case, as well as the inside of the neck if using a mandrel. I spray it liberally enough that wiping it off the outside isn't sufficient, IMO. So I run all the cases through several 5-10 min washes/soaks with Dawn/Lemishine, followed by several rinses with hot water. I typically process 100-200 cases at a time when using this method, so it's really not a huge effort. Cases are then dried as normal before further processing. I wouldn't leave any lube inside the neck unless you purposely mean to do so, as with graphite or other similar lubricants. In other words, using a mandrel step necessitates lubing the inside of the neck, and you probably want to remove that before any further steps.

So you lube,resize, mandrel, then clean .
At some point do you lube inside of necks before seating bullets?

 

[Ned Ludd]

So you lube,resize, mandrel, then clean .
At some point do you lube inside of necks before seating bullets?

I do not. My brass prep regimen leaves a visible patina on the inside of the necks, and I have never felt the need to use any lube prior to seating bullets.

 

[Papamike]

I do not. My brass prep regimen leaves a visible patina on the inside of the necks, and I have never felt the need to use any lube prior to seating bullets.

Thank you sir.
I am fairly new to F T/R and I have learned very much from your posts here. I make it a point to read everything you put out on here.