Tell me about mandrels? Use of, pro & con

they're pricy, but I've started using the SAC modular sizing dies with the expander mandrel installed, and it has worked very well and minimized the number of steps for me.


 
I think I wrote RCBS earlier but, the die I use is (from the label on the box) a Redding Type S - Bushing Style Full Sizing die. Part number 77136 for the 7mm Remington Mag. The neck bushing goes in the die. You can change bushing size to minimize how much sizing you do. The mandrel die comes from 21st Century. Most of my mandrels come from them too. I also have Short Action Customs and Cortina Precision mandrels. The 21st Century mandrels are good enough for what I do.
 
I used full length and neck bushing dies for decades until a few years ago. Now I use full length dies with the expander ball removed, bump shoulders .002 and then expand with a
mandrel. A little graphite makes it work very easy and produces more consistent ammunition in my opinion. I also anneal every couple of firings to prolong the brass life. But I try to only use quality brass which is more expensive.
 
It's an added step and I have learned to accept that for precision ammo. For plinking etc, I don't.

There is a lot to think about but in the end don't overthink it. The only real con is the extra time. Concentric necks. Uniform inside diameter. Consistent expansion on non turned necks. Better control of desired tension. All worth the little investment and time for me.
 
I full length resize for everything that I reload for. I use Sinclair mandrel die for everything that I reload for except the straight walled cartridges, I use the expander/bell mouth die for them. I remove the expander ball from the full-length resizing die, so this adds an additional two steps to the reloading process if you are reloading cases that have been fired. For depriming a use a Lee universal priming tool. When using a mandrel for neck sizing, the mandrel also removes the "donut" if the case has one. My thoughts on the donut are there are two ways to remove it, resize and ream the excess brass off, or expand the brass from the inside of the case outwards and turn the neck of the casing. I prefer turning the neck of the case to maintain concentricity of the brass on the case neck. I use a Foster, Original case with a neck turning attachment. I have found that with the Foster turning tool the neck also is getting trued up with the case body. I hope this helps.
 
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Would like to learn all about mandrels when to use them how to use them . Why they do for your brass etc Thanks to you all for your help. Teiy
I use the 21st Century.

21st Century expander die.jpg

21st Century expander dies with and without window.jpg


These videos provide an excellent explanation ...





 
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These were reccomended by Pieter Milan of Impact Shooting. You might want to take a look at this set that I use. They are out of South Africa. It's great kit, the prices are very reasonable, shipping prices are reasonable and shipping time was great. You get the whole set, not one piece at a time.
 
These were reccomended by Pieter Milan of Impact Shooting. You might want to take a look at this set that I use. They are out of South Africa. It's great kit, the prices are very reasonable, shipping prices are reasonable and shipping time was great. You get the whole set, not one piece at a time.
WOW, Do you get 12 exp.mandrel and the die for 130.00
Did I read that right.
 
These were reccomended by Pieter Milan of Impact Shooting. You might want to take a look at this set that I use. They are out of South Africa. It's great kit, the prices are very reasonable, shipping prices are reasonable and shipping time was great. You get the whole set, not one piece at a time.
Thats's a heck of a deal.
 
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