Sinclair expander die?

[Okiecat]

I just purchased a Sinclair expander die with a E-22 mandrel. I was wanting to expand some new Lapua brass, so I could turn the necks with my K&M neck turner. The mandrel on the Sinclair measures .2235 and the mandrel on the K&M turner measures .224. I don't see how this is going to help. I would have thought the expander mandrel would have been at least .2245 or even bigger. This would seem to be the minimum for clearance on the neck turner mandrel.

 

[tightneck]

K&M makes an expandiron that is for use with its neck turner. The Sinclair expander mandrels are to be used in conjunction with Sinclair neck turners.

 

[Bobs243Ackley]

The Sinclair neck turning mandrels are .002" smaller than bullet diameter, and the expander mandrels are .001" smaller than bullet diameter. This is done to allow for the spring back of the brass necks. This only allows about .00025" clearance, and the lube will take up the rest of the clearance. This sets up the case to run on the mandrel without having to struggle to get in onto the neck turning mandrel. I hope this information will help everyone.

Cordially,
Bob Blaine

 

[Okiecat]

So Bob what you are saying is that I wasted my money buying the Sinclair expander die, and now I have to buy a K&M expander die and mandrell.

 

[mikecr]

You could get a Sinclair turner. Nothing wrong with them.

I like the Sinclair expander dimensions and system. Very useful in reloading. If nothing else it leaves the necks at the right tension for reloading without having to follow with neck sizing,again). I run the mandrels through all necks prior to bullet seating to reduce runout. I use their mandrels to upsize necks for various cartridge forming.
It's a well thought out system IMO.