Expanders

[dbaird]

Which do you prefer to expand cases with-
Case expanders (PMA, 21’stCentury)
Whidden expander in their dies
Expander pins?

 

[RustyInBend]

Definitely the 21st Century Mandrel Kits ... I have them for 6.5-CM, 30-cal, and 338. Well-made, and results in great concentricity and super low runout.

 

[jepp2]

For setting neck tension prior to loading, I use 21'st Century mainly because the steps they offer them in, but that might be more than necessary.

For setting necks for turning I use Sinclair mostly, but some 21'st Century. I like the ones that are coated as the bare SS tends to pick up brass.

I never went for the gauge pin method mostly because I didn't have a way to eliminate the sharp break at the corner.

 

[MarkTrew]

 

[DocBII]

Mark Trew,

So what is it?

Thanks,
DocBII

 

[MarkTrew]

Sorry, this link was supposed to be included.

Mandrel Dies – Porter's Precision Products

portersprecisionproducts.com

the great thing about this is the almost infinite number of size options.

MarkTrew

 

[6Creed73]

21st century die/mandrels hands down. Very smooth expanding and they have many sizes for each caliber.

 

[MarkTrew]

Okay, let’s look a moment. The 21st Century pins are turned down and available in half thousandth increment, looking at the website.

Porter uses commercial gage pins. Let’s have a reality check as to what is available using just the McMaster Carr picture as an example, using the picture. The material for the expander is the same for 21st or the gage pins. Having tried both the 21st, Porter , K&M and an older Sinclair I have settled on the Porter. I think you will find it is the best option that is available.
MarkTrew

 

[Trevor60]

Turning cases i use the Sinclair with carbide turning and expanding mandrels

Expanding cases from neck sizing I found the Forster Universal bullet puller with a caliber specific collet, worked well. Collets and pins are sold separately, and you would need to hone the pins .
If I am foruntate after testing, (neck tension) the pin guage dia is the same size as one of my sinclair carbide mandrels.

 

[6.5 forever]

Sinclair carbide works for me. I think all of them will work well

 

[6Creed73]

Okay, let’s look a moment. The 21st Century pins are turned down and available in half thousandth increment, looking at the website.

Porter uses commercial gage pins. Let’s have a reality check as to what is available using just the McMaster Carr picture as an example, using the picture. The material for the expander is the same for 21st or the gage pins. Having tried both the 21st, Porter , K&M and an older Sinclair I have settled on the Porter. I think you will find it is the best option that is available.
MarkTrew

I looked at the Porter when I was shopping for expanders...they look like good quality. But where 21st Century wins imo, is cost. With Porter you have to buy pins and collets for each caliber, with 21st Century you just buy the mandrel/pin. And the die body is less expensive. Also like that the 21st Century mandrels are just drop in...very easy to swap.

 

[marchboom]

I use a Forster bullet puller and gauge pins to set the neck I.D. Seems to work very well.

I like the Porter pin holder and maybe someday I'll get one. Just wondering if concentricity is better with the Porter collet holder.

 

[BigBolt]

I just keep things simple and buy matched die sets for each round each comes with their own expander.

 

[mikecr]

I've always used the Sinclair expander die/mandrel system for neck turning, and pre-seating expansion.
I like my mandrels floating,, nothing rigidly held.
Sinclair's GEN II expander die floats mandrels, and would accept PMA mandrels, I'm pretty sure.

 

[marchboom]

Not to hijack this topic but that brings up another issue. Is it better to have the mandrel floating or solidly mounted in the collet?

 

[RegionRat]

My conclusion was it didn't really matter if the mandrel was floating or rigid constrained so long as the pin runout when constrained wasn't gross.

The brass is only held by the shell holder, which offers much freedom to self align. A pin would have to be very grossly misaligned to use up all the freedom in the shell holder.

Between the precision and accuracy of the parts, gross misalignment would have to be from damage or getting debris trapped inside alignment surfaces of the die.

Just make sure nothing works loose if you play with floating the pin since not all designs clamp or tighten the same way. YMMV

 

[swd]

Another vote for the Porter. No proprietary mandrels. And you can get gage pins as fine as .0001” if you so desire. And you can get them from Amazon, McMaster Carr and many other tool stores. Each collet covers range of many calibers.

 

[3Sigma]

Sorry, this link was supposed to be included.

Mandrel Dies – Porter's Precision Products

portersprecisionproducts.com

the great thing about this is the almost infinite number of size options.

MarkTrew

Nice. Using modified ER collets and pin gauges. And an adapter to use in a press.

Not a bad idea.

I like to try techniques before I invest. I used a belt sander to round off some pin gauges and used a Hornady collet bullet puller as a makeshift collet to hold the pins.

Find my desired tension with the pins, then bought a Wilson mandrel die. It can use Sinclair mandrels as well.

 

[6Creed73]

Find my desired tension with the pins, then bought a Wilson mandrel die. It can use the 21st century mandrels as well.

Are you saying the Wilson die can use the 21st Century mandrels? I have both and the 21st Century mandrels aren't compatible with the Wilson die, unless something changed.

 

[3Sigma]

Are you saying the Wilson die can use the 21st Century mandrels? I have both and the 21st Century mandrels aren't compatible with the Wilson die, unless something changed.

My bad, it is compatible with Sinclair. I'll correct it. Thank you