Using a mandrel to size necks

[Dirtdevil]

Ok guys got a questions for the experts. Looking to make my loads as consistent as possible . What is your thoughts on sizing without an expander ball and then running a mandrel in the neck to set your neck tension. Can you even buy mandrels of different sizes and if so where. Or is it better to just size with a bushing die without an expander ball. Any input is appreciated. Thanks In advance great info on this site

 

[dok7mm]

I use FL, non- bushing dies with expander ball removed, but I set my neck tension with K&M expander mandrels, available in .0005" increments. Works great!

 

[ar10ar15man]

i size them down and then expand up with a mandrel....do not pull buttons.
as a generic rule some where between .001 and .003 under

 

[jimbires]

I like to use a mandrel for neck expanding .21st century now has them available .

http://www.xxicsi.com/expander-mandrels.html

 

[antelopedundee]

Oftimes I simply let the bullet do the expanding.

 

[cape cove]

If your objective is reduced neck run-out then a Redding body die to size your case and bump your shoulder and a Lee collet die to size the neck works great, an inexpensive set up. You then use a seater die of your choice to seat your bullet. Forster makes great seater dies. JMO

 

[Dirtdevil]

As always great info here. Thanks I will try this. Main goal is to ditch the expander ball and control the amount or neck tension. Seems like this method is the answer

 

[antelopedundee]

As always great info here. Thanks I will try this. Main goal is to ditch the expander ball and control the amount or neck tension. Seems like this method is the answer

I assume you will be turning your case necks to a uniform wall thickness, otherwise the above efforts won't be of that much value.

Also regardless of whether or not you use a FL die sans expander or a bushing die, you can use the neck turner mandrel as an expander mandrel with the proper setup.

 

[ar10ar15man]

not exactly true
a better fit is just that.
yes life is better with turned necks
and even partial like a 50% contact cut will help.
pulling necks is a known source of bent necks, so just skipping that helps.

I assume you will be turning your case necks to a uniform wall thickness, otherwise the above efforts won't be of that much value.

 

[aushunter1]

Oftimes I simply let the bullet do the expanding.

The only problem with that I find is when seating (even with comp seater) I get different seating depths due to inside dimentions being different.
Imo if you use a mandrel the inside diameter should be more consistent helping seatind & projectile seating tension.

 

[antelopedundee]

The only problem with that I find is when seating (even with comp seater) I get different seating depths due to inside dimentions being different.
Imo if you use a mandrel the inside diameter should be more consistent helping seatind & projectile seating tension.

If your necks are of uneven thickness then sizing without an expander moves the out of roundness condition to the inside, but the uneven neck tension still remains.


FWIW, Redding advises against using the competition seater to seat bullets into cases where the neck has been sized down but not expanded.

 

[aushunter1]

If your necks are of uneven thickness then sizing without an expander moves the out of roundness condition to the inside, but the uneven neck tension still remains.


FWIW, Redding advises against using the competition seater to seat bullets into cases where the neck has been sized down but not expanded.

Yeh its probably an annealing issue to at times.

That's interesting from Redding, never heard or read that before!
Would that be to probably more pressure needed to seat & not good for the stem?

 

[antelopedundee]

Yeh its probably an annealing issue to at times.

That's interesting from Redding, never heard or read that before!
Would that be to probably more pressure needed to seat & not good for the stem?

https://redding-reloading.com/tech-line-a-tips-faqs/168-working-with-your-competition-seating-die

From the link. Intended for compressed loads, but applies to tight necks also I'm told.

"To hold the bullet concentrically, the Bullet Alignment Bore and the Seating Stem have been honed and ground to virtually the same diameter as a jacketed bullet. As a result, the seating stem walls are relatively thin and not as inherently robust as the Seating Plug in a standard Seating Die. Though the Stem is heat treated to make it as strong as possible, it will not endure the excess seating pressure of Compressed Charges. This excess seating pressure will crack the Seating Stem which will, in turn, damage the other internal parts of the Die. Please be mindful because replacement parts are costly and NOT covered under Warranty. Please remember that your Competition Seating Die is a precision instrument and should be used and treated as such. A handloader using this Die to compress powder is tantamount to a machinist using a Micrometer as a C-Clamp."

 

[aushunter1]

https://redding-reloading.com/tech-line-a-tips-faqs/168-working-with-your-competition-seating-die

From the link. Intended for compressed loads, but applies to tight necks also I'm told.

"To hold the bullet concentrically, the Bullet Alignment Bore and the Seating Stem have been honed and ground to virtually the same diameter as a jacketed bullet. As a result, the seating stem walls are relatively thin and not as inherently robust as the Seating Plug in a standard Seating Die. Though the Stem is heat treated to make it as strong as possible, it will not endure the excess seating pressure of Compressed Charges. This excess seating pressure will crack the Seating Stem which will, in turn, damage the other internal parts of the Die. Please be mindful because replacement parts are costly and NOT covered under Warranty. Please remember that your Competition Seating Die is a precision instrument and should be used and treated as such. A handloader using this Die to compress powder is tantamount to a machinist using a Micrometer as a C-Clamp."

Cheers
I will remember that!