Need Advice on Using Expander Mandrels

Just to try something different, I have decided to give this mandrel thing a go. I've always been pleased with the results from using Redding Type S Match full sizing dies with neck bushings and carbide expander buttons, but want to see if removing the expander and using a mandrel instead will have any effect on ES and SD.

I'm looking at the 21st Century die with the window and their caliber specific mandrels. I'm not ready to go all out on the mandrel kits so where should I start? How far do you size down with a bushing and then what size mandrel would you run through to get around .002 neck tension? Say I'm sizing ADG brass for a 7 SS, would a .283 mandrel give me the desired tension with spring back?
Take a look at porter precision gage pin expander. Exceptional product.
 
I never use mandrels unless I have no choice. They overwork the brass and shorten its life. If available I use a Redding Body Die and a Lee Collet Die. My primer pockets go well before I have problems with neck cracking or case separation. Very consistent accuracy.
 
Just to try something different, I have decided to give this mandrel thing a go. I've always been pleased with the results from using Redding Type S Match full sizing dies with neck bushings and carbide expander buttons, but want to see if removing the expander and using a mandrel instead will have any effect on ES and SD.

I'm looking at the 21st Century die with the window and their caliber specific mandrels. I'm not ready to go all out on the mandrel kits so where should I start? How far do you size down with a bushing and then what size mandrel would you run through to get around .002 neck tension? Say I'm sizing ADG brass for a 7 SS, would a .283 mandrel give me the desired tension with spring back?
K&M expand mandrels are part of my reloading procedures for 6.5 Creedmoor and 6.5 PRC, along with Redding Type S Match full sizing dies (with button removed, of course.) I also use their micrometer seating dies. With neck-turned brass (using K&M apparatus) I get
between zero and .0015" of run-out.
 
I did check into this system, it seems pretty straight up. I tried to figure out what such a set up would cost to get started, cannot quite figure out the initial cost. Would you help me out here.
I considered them, but I went with the 21st Century for their price and options. I am happy with mine, and their CS is excellent.

Porter's long collet is $85 and pins are $10 each

21st Century for the same with ring is $42 and SS expander mandrel are $10.75 each (available nitrided and titanium and with plenty of choices)
 
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Take a look at porter precision gage pin expander. Exceptional product.
^This.
I did check into this system, it seems pretty straight up. I tried to figure out what such a set up would cost to get started, cannot quite figure out the initial cost. Would you help me out here.
Email Mr. Porter and ask for a quote. He got back to me fairly fast. If you are handy then search my recent post on the Porter Precision Mandrel system as you can make the mandrels from gage pins fairly easily. (EDIT: gage pins start at about $7 each right now). I posted at least one such source for the pin. Or you can buy them from Mr. Porter as his pricing for the mandrels is very reasonable.

If you're still convinced that you want to go with the Sinclair tools then PM me as I replaced nearly brand new Sinclair with Porter tools and still have the Sinclair tools sitting around and haven't gotten around to posting a FS ad.
 
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I never use mandrels unless I have no choice. They overwork the brass and shorten its life.
Please explain why you believe this. I find the opposite effect. I use a bushing FL sizing die to size the neck only as much as necessary and then use a mandrel to set final ID. An example is I will use a .290 bushing (assuming .014 neck thickness) and a .262 Mandrel. How is that over working the brass. I have never had a split neck. At least not in the last 20 years. A standard die with a expander button would move the brass neck maybe .010. Does a Lee collet die not have a Mandrel in it?
I am asking because I want to learn not to argue.
Henry
 
Your going to get a lot of advice on this subject. Here's what works for me on my hunting and general purpose rifles

I FL size my brass with the appropriate bushing to give my brass .003-.005" of "neck tension". Then I use a mandrel sized .001" smaller than my bullet diameter and go from there
I do the same
 
If you anneal at least every other firing you can run a case thru a regular full length die and then push it back out with a 1 thou under mandrel (basically overworking the neck as much as is possible) and it will out last a case that's just sized with a bushing die for 2 thou of neck tension and never had a expander ball or mandrel thru it that's never annealed.
 
Please explain why you believe this. I find the opposite effect. I use a bushing FL sizing die to size the neck only as much as necessary and then use a mandrel to set final ID. An example is I will use a .290 bushing (assuming .014 neck thickness) and a .262 Mandrel. How is that over working the brass. I have never had a split neck. At least not in the last 20 years. A standard die with a expander button would move the brass neck maybe .010. Does a Lee collet die not have a Mandrel in it?
I am asking because I want to learn not to argue.
Henry
The Lee Collet Die just pushes the neck in slightly, it does not form or work it a mandrel of sleeve does. There is no lube required for the Lee Collet Die. The Redding Body Die just pushes the shoulders back 3/1000, slightly working the casing body. Need lube for the body die. The neck only gets pushed in, there is no mandrel reforming the neck as the die is being extracted. There is less force required to seat the bullet as well, which I also like. See this video by Bolt Action Reloading on the different forces required to seat bullets.
 
The Lee Collet Die just pushes the neck in slightly, it does not form or work it a mandrel of sleeve does. There is no lube required for the Lee Collet Die. The Redding Body Die just pushes the shoulders back 3/1000, slightly working the casing body. Need lube for the body die. The neck only gets pushed in, there is no mandrel reforming the neck as the die is being extracted. There is less force required to seat the bullet as well, which I also like. See this video by Bolt Action Reloading on the different forces required to seat bullets.

I do not anneal. Need not to as I am minimally working the brass neck. I put about 20# of force for the Collet Die, never more. I have system that controls the force I put into the die. As I said my necks never crack, always my primer pocket loosens. I reload casings about 10 times before I dispose of them. By them some of the primer pockets are loose enough that I don't trust them.
 
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